Gmail7 min read

Test Gmail deliverability for free — without GlockApps

GlockApps's Inbox Insight starts at $59/month after 3 free tests. The full Gmail placement matrix — consumer Gmail, Workspace, all five tabs — is available for free here. Here is how to use it.

If you've been testing Gmail placement for more than a month, you've probably hit the GlockApps paywall. Three free tests, then $59/month for the entry tier. That math stops working the moment you're iterating on a cold outreach template — you want 10 tests a day, not 10 tests a quarter. This article covers what a Gmail placement test needs to do, and how to run it for free.

Pricing comparison

GlockApps Inbox Insight: 3 free tests, then $59/month (Basic), $99/month (Pro), $199/month (Enterprise).

Inbox Check: unlimited free tests. 20+ providers including Gmail, Workspace, Outlook, Yahoo, Mail.ru, Yandex, GMX, Orange, ProtonMail, iCloud, Fastmail, Zoho. Real screenshots. Public API and MCP endpoint.

The three things a Gmail placement test must cover

  1. Folder / tab placement — Inbox (Primary), Promotions, Social, Updates, Forums, or Spam. Per-seed, not averaged.
  2. Authentication verdict — SPF pass/fail, DKIM pass/fail, DMARC alignment, ARC chain validity. Pulled from Gmail's own Authentication-Results header, not simulated.
  3. Content score — SpamAssassin and/or Rspamd on the raw MIME. Not a guess — an actual score with rule breakdown.

Anything less is a deliverability estimate, not a deliverability test. Tools that give you one "deliverability score" from a single number are guessing.

Why ESP "delivered" is not enough

An ESP sees the SMTP conversation. When Gmail's MX server issues 250 2.0.0 OK, the message is "delivered". Tab placement, image caching, link trust-warnings, the Be careful with this message banner — all of it happens inside Gmail after the SMTP session closes. None of it flows back to the sender through any standard mechanism.

Some ESPs (Mailgun, Postmark, SendGrid) expose engagement signals (opens, clicks) that act as a proxy — but opens are unreliable after Apple MPP, and neither proxy tells you which Gmail tab.

Consumer Gmail vs Workspace filtering

They share the core classifier but diverge in important ways:

  • Consumer Gmail has tabs by default (Primary / Promotions / Social / Updates / Forums). Workspace has them off by default.
  • Workspace tenants may have admin-level transport rules, compliance filters and allow/block lists that override the base classifier.
  • Spam threshold is slightly higher on Workspace — i.e. Workspace is a little more forgiving on ambiguous mail, because its user base is business.
  • Quarantine vs Spam folder — Workspace admins can route suspicious mail to an admin quarantine that the user never sees. Consumer Gmail only uses the Spam folder.

A good Gmail test covers both. Inbox Check includes both consumer accounts and Workspace-tenant mailboxes across multiple custom domains.

Running a free test in 30 seconds

  1. Open check.live-direct-marketing.online and click Start test.
  2. Copy the one-shot BCC address. It's live for ~30 minutes.
  3. Send your real message from your real sending setup (ESP, Workspace, custom SMTP — whatever you ship from).
  4. Put the BCC address in the BCC field. The seed fan-out is transparent — each seed receives the message natively.
  5. Watch the results page. Each seed reports within 2–5 minutes, and the matrix fills in live.

Reading the result

The result page has four panels:

  • Placement matrix. Rows = seeds, columns = folder/tab. Green = Inbox/Primary, yellow = Promotions/Updates, red = Spam, grey = not delivered yet or rejected.
  • Auth summary. SPF, DKIM, DMARC verdicts pulled from the receiver-side Authentication-Results header.
  • Content score. SpamAssassin score and top contributing rules. Rspamd score alongside. Actionable — each rule has a fix pattern.
  • Raw + screenshot. Full raw MIME as received, plus a screenshot of the rendered message in Gmail's UI. This is where you catch image blocking, the "Be careful" banner, and message clipping.

GlockApps vs Inbox Check — full comparison

Feature comparison

Price: GlockApps $59–$199/mo after 3 free tests. Inbox Check free, unlimited, no signup.

Providers: GlockApps ~60 seeds, mostly US/EU. Inbox Check 20+ with strong CIS (Mail.ru, Yandex, Rambler) and EU (GMX, Orange, ProtonMail) coverage.

Screenshots: Both. Inbox Check screenshots include the Gmail UI chrome so you see banners and image blocking.

API / automation: GlockApps has an API on paid plans. Inbox Check has a free public API and an MCP endpoint so Claude, ChatGPT and custom agents can run tests autonomously.

Spam engine depth: GlockApps exposes SpamAssassin. Inbox Check runs both SpamAssassin and Rspamd with rule-level breakdown.

Rate limits and API

There are no hard per-user rate limits on the free tier — the system scales on seed capacity, not paywall. For agencies running hundreds of parallel tests per hour, a paid API tier is in progress. For individual senders, teams under 50 people, and any agency under ~500 tests/day, the free tier is the product.

The API mirrors the UI one-for-one: POST a send, GET the result, subscribe to a webhook for completion. The MCP endpoint lets Claude Code and similar agents run tests inside an AI coding session — useful for CI pipelines that check placement before a campaign ships.

Frequently asked questions

Is the free test as accurate as GlockApps?

Yes for Gmail — both use real seed mailboxes and read the Authentication-Results header straight from Gmail. The coverage is different (different seed mailboxes, different geos), but the underlying methodology is the same.

How often can I test?

As often as you need. There is no daily or monthly cap on the free tier.

Can I test Workspace specifically?

Yes. Inbox Check includes both consumer Gmail and Workspace seeds on custom domains. The results page splits them so you see consumer vs business placement separately.

Do you store my test emails?

Yes, for 30 days, attached to the test ID. Only the person holding the test URL can view the raw MIME. After 30 days it is purged.
Related reading

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