Send Test Email: The Complete 2026 Guide for Cold Email

The "send a test email" instruction in most cold email guides is misleading. Hitting send on your own email address, watching it arrive, and concluding "looks good" misses 80% of what a real test should reveal — and the 80% it misses is exactly the part that matters for cold email deliverability.

A real test email tells you whether your messages pass SPF, DKIM, and DMARC at the receiving server; whether authentication is aligned with the visible From address; whether the message lands in the primary inbox vs Promotions vs Spam at major providers; whether your rendering looks the same across Gmail, Outlook, Apple Mail, and mobile; whether your custom variables ({{first_name}}, company name, etc.) actually expand; whether your tracking pixel loads or trips a filter; whether your sending IP is on a blocklist; and how long the message takes to land.

This guide is the canonical "how to actually send test emails for cold email" reference: why test sends matter at scale, how to set up a seed inbox network, what to test on every send, how the major approaches compare, and the ColdRelay built-in test-send workflow.

TLDR — what test sends do for cold email:

• Seed inbox networks validate inbox placement across providers (Gmail, Outlook, Yahoo, Apple, corporate)
• Internal QA test sends validate rendering, variable expansion, link tracking, and time-to-inbox before a campaign launches
• Deliverability validation confirms SPF/DKIM/DMARC pass at the receiving server (headers, not DNS)
• Time-to-inbox under 10 seconds end-to-end signals healthy infrastructure; 30+ seconds signals throttling or routing issues
• The right cadence: test on every new mailbox, every new template, and weekly on active production campaigns

Table of Contents

• Why test sends matter at cold email scale
• Why "send to my own Gmail" isn't enough
• What a real test email reveals
• Setting up a seed inbox network
• Free vs paid seed inbox approaches
• What to test on every send
• The 3 test-send approaches compared
• Comparison: GlockApps vs mail-tester vs manual seed network
• Common test results and what to do
• ColdRelay's built-in test-send workflow
• A pre-launch test routine
• FAQ

Why Test Sends Matter at Cold Email Scale

Cold email is a volume game played against ISP filters, content classifiers, and reputation systems that all evaluate every send. A single bad campaign blast — wrong subject line, broken variable, blocked link, hit blocklist — can drop Postmaster Tools Domain Reputation by a full notch and take weeks to recover.

Test sends are how you catch these problems before they touch real prospects. They have three distinct purposes for cold email:

1. Seed inbox validation

Send a test message to a curated panel of seed inboxes across major providers (Gmail, Outlook, Yahoo, Apple Mail, corporate gateways). Each one tells you where the message landed: primary inbox, promotions, updates tab, spam, or rejected outright. The aggregate is your inbox placement rate — the single most important deliverability metric.

2. Internal QA

Send to inboxes you control to validate that the campaign is ready to ship:

• Rendering across email clients (Gmail web, Gmail mobile, Outlook desktop, Outlook web, Apple Mail, etc.)
• Custom variable rendering ({{first_name}}, {{company}}, {{custom_field_1}} all expand correctly)
• Link tracking (clicks register; tracking pixel doesn't break content classifiers)
• Time-to-inbox (10 seconds end-to-end on healthy infrastructure)
• Reply path (replies route back to the mailbox you actually monitor)

3. Deliverability validation

Send to inboxes where you can read the full message headers. Verify:

• Authentication-Results: spf=pass dkim=pass dmarc=pass
• The sending IP in Received: headers matches your published SPF
• No unexpected relays in the routing path
• TLS-encrypted hops

For cold email at any scale, all three categories of test belong in your weekly routine. Skip them and you'll find out about problems in the next Postmaster Tools update — by which point the damage is done.

For the full picture of what a deliverability test reveals at the DNS layer, see the email deliverability test complete guide.

Why "Send to My Own Gmail" Isn't Enough

The default cold email test routine — send a message to your own Gmail, see if it arrives — only catches the most catastrophic failures (no delivery at all). It misses:

• Soft-fail authentication. Your message might arrive, but if SPF or DKIM is failing softly, your reputation accumulates damage you can't see.
• Inbox vs Promotions vs Spam classification. Arrival isn't the same as primary-inbox placement. A message in Gmail Promotions counts as "delivered" but doesn't get read.
• Single-receiver bias. Your own Gmail is one receiver with one reputation history of you. Test results don't generalize to other Gmail tenants, let alone Outlook, Yahoo, or Apple.
• Pre-existing receiver trust. If you've emailed yourself often, Gmail's per-user filter learns your sender is safe — your test inbox-places fine while real prospects see the message in Spam.
• Variable expansion failures. Your template may have {{first_name}} in a place the test send doesn't catch (e.g., the subject line at certain character positions).
• Per-client rendering bugs. Gmail web renders your email fine; Outlook desktop strips a critical line because of an unsupported CSS property.

The right test sends to multiple receivers across multiple providers, each with a clean filter history relative to your sender. Seed-list networks do this; one-off self-send doesn't.

What a Real Test Email Reveals

1. Authentication results

Open the test email in Gmail → click the three-dot menu → "Show original." Look for the Authentication-Results: header. You'll see something like:

Authentication-Results: mx.google.com;
  dkim=pass header.i=@example.com header.s=default;
  spf=pass smtp.mailfrom=user@example.com;
  dmarc=pass header.from=example.com

All three should say pass. Any of them saying fail or softfail or none is a problem:

• dkim=fail — your DKIM signature doesn't verify. The public key in DNS doesn't match what's signing messages.
• dkim=none — no DKIM signature at all. Your sending tool isn't signing, or DKIM isn't configured.
• spf=fail — your sending IP isn't in your SPF record. Check the IP in the Received: header against your published SPF.
• spf=softfail — your SPF uses ~all (soft fail) instead of -all (hard fail). Switch to hard fail; soft fail is a weak signal cold email shouldn't be sending.
• dmarc=fail — SPF and DKIM might pass individually but don't align with your visible From domain.

For the full breakdown of how to read these, see how ColdRelay auto-configures SPF/DKIM/DMARC and the SPF/DKIM/DMARC setup guide.

2. Inbox placement

Where the message lands at each receiver:

For cold email, you want Primary at every major receiver. Promotions, Updates, or Junk are degraded placements that tank reply rates.

3. Rendering across clients

Email clients render HTML differently. A campaign that looks correct in Gmail web may render with broken links in Outlook desktop, or with missing fonts in Apple Mail. Test rendering on:

• Gmail web — most popular for B2B
• Gmail mobile (iOS) — large share of "first read" actions
• Outlook desktop (Windows) — uses Microsoft Word's rendering engine, breaks lots of CSS
• Outlook web — closer to Gmail behavior
• Apple Mail (iOS/macOS) — strict spec compliance
• Yahoo Mail web — similar to Outlook web

Cold email best practice is plain text or very minimal HTML — which sidesteps most rendering issues by design. If you're sending HTML-formatted cold emails (most senders shouldn't), test every client.

4. Custom variable rendering

Your sending tool's merge tags ({{first_name}}, {{company}}, {{custom_field_1}}) need to expand correctly in every position they appear:

• Subject line (some clients truncate at unexpected lengths)
• Preview text / preheader
• Body opening
• Body middle
• Body closing
• Signature
• Plain-text fallback if you have one

Common bugs: a variable with no fallback that expands to literally {{first_name}} when the field is empty; a variable that breaks the subject-line character limit when the company name is unusually long; HTML-encoding issues when the variable contains an apostrophe.

Always test with edge-case data: empty fields, long company names, names with apostrophes (O'Connor), non-ASCII characters (Müller), and short fields ("Hi" instead of "Hi John").

5. Link tracking and tracking pixels

Cold email best practice: 0–1 links on first touch, no tracking pixels. If you're using tracking (most sending tools do by default), test sends should verify:

• Tracked links resolve to the correct destination
• The redirect domain isn't on a blocklist
• The tracking pixel loads (some classifiers fire on broken tracking pixels)
• Click events register in your sending tool's reporting

For deeper context on tracking and its tradeoffs, see how to write cold emails that get replies.

6. Time-to-inbox

Cold email from properly-configured infrastructure delivers in 5–15 seconds. Significant delays indicate problems:

ColdRelay-provisioned mailboxes consistently deliver in under 10 seconds end-to-end. Outliers above 30 seconds get logged for investigation. For the SMTP-level error codes you might see, check the SMTP errors hub.

7. Routing path

The Received: headers (read bottom-to-top) show every server the message touched between you and the recipient. For cold email, you're looking for:

• A clean path through your dedicated infrastructure — IPs matching your sending domain's published SPF
• TLS-encrypted hops (look for "TLS" or "STARTTLS" annotations)
• No unexpected relays — if there's a hop through a generic cloud IP that doesn't belong to your sending infrastructure, that's misconfiguration

Parse them with the email header analyzer.

Setting Up a Seed Inbox Network

A seed inbox network is a collection of email addresses you (or a paid service) control across major providers, used solely to receive test sends and report on placement. The bigger and more representative the network, the better the placement signal.

Minimum viable seed network (free, 10 minutes to set up)

For solo operators or small teams, a 10-inbox network across major providers is enough:

• 2 Gmail addresses — one free Gmail, one Google Workspace (if you have one)
• 2 Outlook.com addresses — sign up at outlook.com, both treated as separate accounts
• 1 Yahoo address — sign up at mail.yahoo.com
• 1 iCloud address — generate via an Apple ID (@icloud.com)
• 1 ProtonMail address — sign up at proton.me (catches international ESPs)
• 1 Zoho Mail address — proxy for many corporate gateways
• 1 GMX or Mail.com — European traffic proxy
• 1 catch-all on a domain you control — represents unverified/forwarded mail

Send your test to all 10 simultaneously. Manually check each inbox after 60 seconds. Note placement, time-to-inbox, and any rendering oddities.

Mid-tier seed network (50–80 inboxes)

Paid services like GlockApps and ColdRelay's built-in seed-list tests maintain 50–80+ seed inboxes. The expanded coverage adds:

• Multiple Gmail accounts with varied reputation histories
• Multiple Outlook accounts with varied filtering profiles
• Yahoo accounts with both Bulk and Primary placement history
• Corporate-gateway proxy inboxes (Mimecast, Proofpoint, Barracuda)
• International ESPs (Yandex.ru, Mail.ru, GMX, Tutanota)
• Custom-domain inboxes simulating B2B recipients

The mid-tier networks are what cold email teams should rely on for ongoing monitoring. The manual 10-inbox approach is for first-time setup validation only.

Enterprise-tier seed network (200+ inboxes)

GlockApps' premium tiers and dedicated deliverability consultancies maintain 200+ inboxes for the largest senders. Diminishing returns above ~80 — the placement signal is well-established at that sample size.

How to keep your seed network clean

A seed inbox network is only useful if it has a clean reputation relative to your sender. If you've been emailing your seed Gmail account for 2 years, Gmail's per-user filter learns your sender is safe — your test results will look better than real recipients see.

Best practice:

• Rotate seed inboxes every 6–12 months (paid services do this; manual networks need to be refreshed)
• Never send anything except test emails to seed inboxes (no real outreach, no personal email, no signups)
• Mark seed inbox emails as "Not Spam" when they land in spam — but don't artificially boost them with manual moves between Promotions and Primary (defeats the purpose)
• Read each seed inbox's filter history — Gmail shows this in "Show original"; spam-flagged seed inboxes are no longer useful

Free vs Paid Seed Inbox Approaches

For most cold email teams in 2026:

• 0–5 mailboxes: manual 10-inbox network is enough.
• 5–50 mailboxes: either GlockApps for standalone, or ColdRelay's built-in seed tests if on the infrastructure.
• 50+ mailboxes: ColdRelay's daily seed tests bundled with infrastructure, or Folderly if you want managed.

For a deeper read on mail-tester's specific approach, see mail-tester for cold email.

What to Test on Every Send

Three categories of test, run at different cadences:

Pre-launch test (every new mailbox, every new template)

Run before any campaign goes live:

1. Authentication validation: Run the free deliverability test on the sending domain. All checks must pass.
2. Seed inbox send: Send your template (with realistic merge-tag data) to your 10-inbox seed network. Verify Primary placement at Gmail and Outlook.
3. Headers spot-check: Open the message in Gmail, view the original, confirm Authentication-Results: spf=pass dkim=pass dmarc=pass.
4. Rendering check: Open the message in Gmail web, Gmail mobile, Outlook desktop, and Apple Mail. Verify formatting is intact.
5. Variable expansion check: Confirm all merge tags expanded; no literal {{first_name}} strings; no character-limit overflows.
6. Link / CTA validation: Click every link in the test message. Verify destinations are correct, redirect domains aren't on a blocklist.
7. Reply path check: Reply to the test message. Verify the reply routes back to a mailbox you monitor.

Production weekly test

Run every Monday on active campaigns:

1. Seed inbox send: Send the active template to your seed network. Compare placement to baseline.
2. Blocklist scan: Use the free blacklist checker on sending IP and domain.
3. Postmaster Tools check: Verify Domain Reputation is still High — see the Postmaster Tools for cold email guide.
4. Bounce rate spot-check: Per-mailbox bounce rate above 1% requires investigation.

Incident response test

Run when something breaks (open rate drop, reply rate drop, Postmaster reputation drop):

1. Full deliverability test at /tools/email-deliverability-test.
2. Seed inbox send to confirm placement regression.
3. Header analysis on a recent message to a real prospect (ask them to forward it with full headers).
4. Blocklist scan across the IP blacklist tools and domain blacklist tools.
5. Bounce code review at SMTP errors hub.

The 3 Test-Send Approaches Compared

Approach 1: The free 30-second test

Use ColdRelay's deliverability test tool. Enter your sending domain. The tool runs SPF / DKIM / DMARC / MX / PTR / BIMI / MTA-STS record verification, blocklist scan, TLS support check — all DNS-layer.

Best for: Initial setup validation, pre-launch sanity check, debugging a domain that suddenly stopped landing.

Doesn't cover: Inbox placement, rendering, variable expansion, real-recipient reputation.

Approach 2: Send to your own multi-provider inboxes

Manually send a test email from your cold email setup to addresses you control at Gmail, Outlook, Yahoo, Apple Mail, and a custom-domain test inbox. For each, open the message and check Authentication-Results header + inbox placement.

Best for: Per-template validation, rendering checks, variable expansion verification.

Doesn't cover: Inbox placement at receivers other than your own accounts (your own Gmail filter knows you; real prospects' filters don't).

Approach 3: Seed-list inbox placement test

For ongoing diagnostic, use a seed-list service: GlockApps (industry standard), Folderly, or ColdRelay's built-in daily seed tests. These send to a pre-configured panel of seed inboxes (typically 50–90 inboxes across major providers) and report per-provider placement.

Best for: Weekly monitoring, regression detection, comparison across templates.

Doesn't cover: Per-template QA (you should still spot-check rendering and variables manually).

Comparison: GlockApps vs mail-tester vs Manual Seed

The three most-cited test approaches, head-to-head:

When mail-tester is enough

mail-tester is most useful when you want a quick "is this specific template likely to spam-trigger?" check on content alone. Its 0–10 score reflects:

• Authentication setup
• Content spam-trigger words
• Link reputation
• Blocklist status
• Sender reputation indicators

A mail-tester score of 8/10 or higher is the baseline; below 7/10 needs work before sending at volume. Useful for testing template changes; less useful as a continuous monitoring tool because the score is one moment in time.

When GlockApps is enough

GlockApps is the gold-standard for per-provider placement reporting. If you need to know "at Gmail specifically, did this campaign hit Primary or Promotions?", GlockApps tells you. Use it when you're running enough volume to justify the $59–$199/month and you don't have a built-in seed network from your infrastructure.

When manual seed is enough

The 10-inbox manual network is enough for solo operators, freelancers, and brand-new domains where you want to validate setup before spending on paid testing. It catches binary "is it broken" issues. It does NOT scale past a handful of campaigns per week — the manual inspection overhead becomes prohibitive.

When ColdRelay's built-in is enough

If you're on ColdRelay infrastructure, the dashboard runs daily seed-list placement tests across 50+ inboxes automatically. No subscription, no manual triggering. You get per-domain placement reporting that updates daily, with alerting on regression. For most ColdRelay customers, this fully replaces standalone GlockApps subscriptions.

Common Test Results and What to Do About Them

"Test email arrived in Spam at Gmail"

Diagnose in order:

1. Check Authentication-Results. If SPF, DKIM, or DMARC is failing, fix authentication first — content optimization is wasted while auth is broken. See how to read auth headers.
2. Check Google Postmaster Tools. If Domain Reputation is Low or Bad, the issue is reputation accumulation — pause and rebuild over 2–4 weeks at reduced volume. See the Postmaster Tools for cold email guide.
3. Check the message body for spam triggers. Excessive ALL CAPS, multiple exclamation marks, URL shorteners, suspicious link destinations. Rewrite if any are present.
4. Check the From address. Cold email from no-reply@ or info@ addresses underperforms personalized From names (firstname.lastname@ format).

"Test email arrived in Promotions at Gmail"

Promotions is Gmail's "marketing-pattern" classification. Cold email shouldn't trigger it. Causes:

• Heavy HTML formatting (text-only or minimal-HTML cold email is the standard)
• Multiple images in the body
• Promotional language ("free trial", "limited time", "special offer")
• Suspicious link patterns (URL shorteners, tracking pixels, multiple destinations)
• Volume pattern that looks like a marketing blast (10,000+ identical messages in a window)

Cold email should look conversational and lightly-formatted. If your message lands in Promotions, the content classifier is reading it as marketing email.

"Test email arrived at Gmail but delayed 5+ minutes"

Common cause: receiver is greylisting your sender. ColdRelay's retry logic resolves over 99% of greylisting on the first retry. If you're seeing chronic delays, check:

• DNSBL status — your IP might be on a list that causes rate-limited delivery
• DNS PTR record — missing or generic PTR signals "transient cloud instance" and triggers receiver-side caution
• Volume pattern — too aggressive a ramp from a new IP triggers throttling

"Test email arrived at Gmail but not at Outlook"

Outlook's deliverability dynamics differ from Gmail. Common causes:

• Microsoft SNDS shows red/yellow IP status. Check SNDS and address whatever it's flagging.
• Outlook-specific blocklist entry (different DNSBLs than Gmail uses)
• Outlook's content classifier is stricter on specific link patterns
• PTR record mismatch — Outlook weights PTR validation more heavily than Gmail

For cold email, both Gmail and Outlook need to inbox-place. If only one works, the other is silently dropping reply rate.

"Variable expanded as literal {{first_name}}"

Bug in your sending tool's merge logic. Causes:

• Field is empty in the contact record and there's no fallback configured
• Typo in the variable name ({{first_name}} vs {{firstname}} vs {{first-name}})
• The variable isn't in the recipient list mapping
• HTML encoding issue ({{ becoming {{)

Fix in the sending tool. Always test with a contact record that has every field populated, then re-test with a contact record where most fields are empty.

"Variable broke the subject-line character limit"

Common cause: a long company name pushes the subject past 60 characters (where most mobile clients truncate). Fix by capping the variable's character length at template-design time, or by using shorter variable values.

"Tracking pixel didn't load"

Either your tracking domain is on a blocklist, or the recipient's email client is image-blocking by default (Apple Mail, increasingly Gmail). Image-blocking by Apple Mail Privacy Protection is the most common cause and not actually a problem — the pixel will load when Apple's pre-fetcher hits it, just not in real-time.

For deeper context on tracking and the open-rate measurement problems Apple MPP creates, see the good open rate guide.

ColdRelay's Built-In Test-Send Workflow

The ColdRelay dashboard includes a "Send test" button per mailbox that fires a templated test email to any address you specify. The dashboard surfaces:

• Authentication-Results header — full SPF, DKIM, DMARC pass/fail breakdown
• Time-to-inbox — end-to-end delivery latency
• TLS handshake confirmation — TLS version, cipher
• Routing path — every relay the message touched
• Inbox placement (if you specified an address in our seed network) — Primary / Promotions / Spam classification

In addition, ColdRelay runs daily seed-list placement tests automatically across 50+ seed inboxes for every connected sending tool (Instantly, Smartlead, EmailBison, Saleshandy). The placement report shows up in the dashboard with per-provider breakdowns and alerts on regression.

The "automated test" feature means you don't need a separate GlockApps subscription if you're running on ColdRelay — the same seed-list testing is built in. ColdRelay's pricing is per-mailbox flat: $1.00 (1–199 mailboxes), $0.85 (200–999), $0.70 (1,000–4,999), $0.55 (5,000+) — and the test-send infrastructure is bundled in that price.

For the underlying authentication that makes these tests pass reliably, see how ColdRelay auto-configures SPF/DKIM/DMARC.

A Pre-Launch Test Routine

Before turning on a new cold email campaign on a new domain:

1. Run the free deliverability test on the sending domain. All DNS checks must pass.
2. Send a manual test email to your 10-inbox seed network (or the larger one you maintain). Verify Authentication-Results all pass; verify Primary inbox placement (not Promotions, not Junk).
3. Open the message in Gmail web, Gmail mobile, Outlook desktop, and Apple Mail. Verify rendering across clients.
4. Verify variable expansion in a sample test send using realistic merge-tag data (long company names, names with apostrophes, empty fields).
5. Check Google Postmaster Tools 48 hours after first sending. Domain Reputation should land at Medium or higher.
6. Check Microsoft SNDS if Outlook traffic matters for your ICP.
7. Run a blacklist scan on your sending IP weekly thereafter.

This 15-minute routine catches over 90% of deliverability and rendering problems before they ruin a campaign.

For the cold email content side — how to write copy that doesn't trigger spam classifiers in the first place — see how to write cold emails that get replies and the cold email template generator.

FAQ

How is sending a test email different from running an email deliverability test?

A test email = sending a real message and observing its journey. A deliverability test = running diagnostic checks on your DNS, authentication, blocklist status, etc. without sending mail. They complement each other. Run the deliverability test before launching to catch setup issues; send test emails to specific multi-provider inboxes during ongoing operations to spot-check actual placement. See the email deliverability test complete guide for the DNS side.

Should I send a test email from every mailbox before launching campaigns?

Yes — at least one test send per mailbox in the first week. The per-mailbox test catches authentication issues that aggregate dashboards miss (e.g., a single mailbox's DKIM not signing because its mailbox-specific config is wrong). After the first week of clean sending, per-mailbox testing becomes redundant.

Can I send a test email to a spam-trap address?

Don't. Spam traps are addresses set up by anti-spam services specifically to catch senders who scrape lists or buy from low-quality data sources. Sending to a trap is one of the fastest ways to land on Spamhaus SBL. Only send to addresses you confirmed legitimately.

What's the difference between SPF=pass and DMARC=pass?

SPF=pass means your sending IP is in the SPF record for the "envelope from" domain (the address the receiving server sees during the SMTP transaction). DMARC=pass means SPF+DKIM are aligned with the "header from" domain (the address visible to the recipient). Both can pass independently while DMARC fails — that's the alignment-failure scenario most cold email setups don't realize they have.

Why is my test email's Authentication-Results header showing dkim=temperror?

Temporary DNS lookup failure. Usually transient — re-send the test in 5 minutes. If it persists, your DKIM DNS record might have propagation issues or formatting problems. Check the record via dig +short TXT default._domainkey.yourdomain.com.

Does ColdRelay let me send test emails from the dashboard?

Yes — there's a "Send test" button per mailbox that fires a templated test email to any address you specify and surfaces the Authentication-Results header in the dashboard. Useful for verifying a freshly-provisioned mailbox before adding it to a real campaign. In addition, ColdRelay runs daily seed-list inbox placement tests automatically across 50+ seed inboxes for every active mailbox, with alerts on regression.

How many seed inboxes do I need for an accurate placement read?

10 is the practical minimum for binary "is the campaign broken" reads. 50+ is the sweet spot for ongoing monitoring (per-provider placement granularity). Above 80, diminishing returns — additional inboxes don't materially improve the placement signal.

Should I test from the production mailbox or a separate test mailbox?

Production. The reputation of the test sender is part of what you're validating. A separate "test" mailbox with no warm-up history will produce results that don't generalize to production. Test from the actual mailbox you'll be sending from, at the actual canonical 4/day cap (2 outbound + 2 warmup).

How often should I refresh my seed inbox network?

Every 6–12 months. Seed inboxes accumulate "I trust this sender" reputation history over time, which biases their placement decisions. Rotating in fresh inboxes keeps the placement signal clean. Paid services (GlockApps, ColdRelay) handle this automatically.

Can a test email tell me if my domain is on a corporate gateway blocklist (Mimecast, Proofpoint, Barracuda)?

Only if your seed network includes proxy inboxes behind those gateways. Most free seed networks don't; paid services like GlockApps and ColdRelay maintain coverage. If your ICP is enterprise-heavy, prioritize seed inbox coverage at corporate gateways over additional consumer-ISP inboxes.

A test email is a diagnostic, not a delivery confirmation. Read the Authentication-Results header, check inbox placement across multiple receivers, validate rendering and variables, and use the free tools to confirm the underlying setup.

Run the free 30-second deliverability test → /tools/email-deliverability-test · Cold email infrastructure that passes every test → Try ColdRelay free · Plan your campaign → Cold email template generator