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Email Spam Tester vs GlockApps
GlockApps is a paid deliverability platform for teams that test every campaign. If you need a placement test now and then, a free one may be all you need.
Pick Email Spam Tester if
- you test now and then and do not want a subscription or credits that expire
- you want to start without creating an account
- you need the Gmail and Yahoo bulk-sender rules and one-click unsubscribe checked
- your team works in a language other than English
Pick GlockApps if
- you need a large seed list with regional providers in many countries
- you want spam scores from corporate filters such as Barracuda, Microsoft EOP and Proofpoint
- you want scheduled tests with alerts in Slack or PagerDuty, DMARC analytics and uptime monitoring
- you report to clients with white-label PDFs
Run both tests on the same email
The fairest comparison is your own message. Get an address, send the email you were going to test anyway, and put the two reports next to each other.
Side by side
| Feature | Email Spam Tester | GlockApps |
|---|---|---|
| Start | Open the page and send | Create an account |
| Free tests | No cap on the first 100,000 reports, then 5 a day per IP | 2 full tests, once |
| No-account checker | The full test | 3 a day, Gmail, Yahoo, AOL and Outlook, SpamAssassin only |
| Seed inboxes | Gmail, Outlook, Yahoo and other providers | 115+ across 27 named providers (“30+” others on its API page) |
| Spam filters | SpamAssassin, Rspamd and an AI judge | Five on its spam-testing page (SpamAssassin, Barracuda, Microsoft EOP, Proofpoint, a Google filter); three named on its home page |
| Technical checks | 42, including bulk-sender rules | SPF, DKIM, DMARC, rDNS, HELO, blocklists, content, links, HTML |
| Bulk-sender rules, one-click unsubscribe | Yes | Not mentioned on its pages |
| Blocklists | 21 | 50+ |
| Monitoring and alerts | No | Yes |
| API | Free | All plans; each test uses a credit |
| Price after the free tests | Nothing | $16.99 for 3 tests, or from $85/month for 30 |
| Unused tests | Not applicable | Do not roll over; packs expire in 1 to 3 months |
| Languages | 31 | English site |
After the two free tests
A new GlockApps account gets two full tests, once. After that every test costs a credit: $16.99 buys three that expire in a month, and subscriptions start at $85 a month for 30 tests that do not roll over. Its no-account checker allows three tests a day, but only shows Gmail, Yahoo, AOL and Outlook and scores with SpamAssassin alone.
For an agency running placement on every campaign, those prices are reasonable. For someone who changed a DNS record and wants to know if it helped, they are a lot of friction for one answer. Email Spam Tester gives that answer without an account, with no daily cap while the first 100,000 reports last and five tests a day per IP after that.
GlockApps
Where GlockApps is ahead
Its seed list is bigger: 115+ inboxes at 27 named providers, including Mail.ru, Yandex, Seznam, Naver and several German and Polish ones. It runs your message past corporate filters, Barracuda, Microsoft EOP and Proofpoint, which tells a B2B sender something this tool cannot. And it is a platform: scheduled tests, alerts in Slack, Telegram or PagerDuty, DMARC analytics, uptime and blocklist monitoring, white-label reports.
If that is what you need, it is the better tool. The website does not monitor anything and has no team accounts.
Email Spam Tester
Where this one is ahead
The report checks things GlockApps' pages do not mention: the Gmail and Yahoo bulk-sender rules as a group, the List-Unsubscribe header and its one-click version, preheader text, link reputation. Most checks quote the RFC section or the receiver's own page they are based on, so you can see why something is flagged.
And it starts without a form. Open the page, copy the address, send. The interface and the reports exist in 31 languages.
What people who tried it said
I took a closer look at it, and it convinced me. […] Every warning names the RFC section behind it. You don't have to believe the tool, you can check it.
Translated from GermanIch habe ihn mir genauer angesehen, und er hat mich überzeugt. […] Jede Warnung nennt die zugrunde liegende RFC-Stelle. Man muss dem Tool nicht glauben, man kann es nachprüfen.
Philipp ZöldEmail deliverability consultantlinkedin.com If you send emails and you don't know where they land, it's a simple first check. And it costs nothing.
Vincent RobinCo-founder, My Deliverability Expertlinkedin.com I just tried your tool and I really like it - good job!
Georg LauterbachMaintainer, docker-mailservergithub.com Questions
Is there a free alternative to GlockApps?
Email Spam Tester shows inbox placement at Gmail, Outlook, Yahoo and other providers and runs 42 checks, free and without an account. It does not replace GlockApps' monitoring, corporate filter tests or very large seed list.
How much does GlockApps cost?
After two free tests, $16.99 for a pack of three tests valid one month, or subscriptions from $85 a month for 30 tests ($59 a month billed yearly). Prices are in USD and taxes may apply.
Does GlockApps have an API?
Yes, on every plan including the free one, and it also runs an MCP server. Each test started through the API uses a credit. Email Spam Tester's API and MCP server are free.
Why do placement results differ between tools?
Seed inboxes have no history with you as a sender (GlockApps calls its seed list a cold audience), so providers can treat them differently from your subscribers' mailboxes. Different tools use different inboxes, so expect them to disagree on single seeds and agree on clear problems.
Other comparisons
All comparisonsRun both tests on the same email
The fairest comparison is your own message. Get an address, send the email you were going to test anyway, and put the two reports next to each other.