MailReach Spam Test: What It Checks, How to Run It and How to Read the Score

The MailReach spam test is a seed-list inbox placement test: you send your real email to a list of 30+ MailReach inboxes, and you get a score, a map of where the email landed at each provider, and a list of content and setup issues to fix. It is free for up to 3 tests per 24 hours, and paid credits add automation, history and alerts. This guide covers the documented steps and how to read the result; for the warmup side of the product, see our MailReach review.

Some tool links here are affiliate links (disclosure). Nerdy Joe is a MailReach affiliate. We did not test MailReach hands-on for this article, and there are no screenshots here; every step and limit comes from MailReach's spam test page, its pricing page and its API docs, listed in the sources at the end.

MailReach spam test at a glance

What the MailReach spam test is

A seed-list test answers one question: when you send this exact email from this exact setup, where does it land? You send to a set of inboxes the tool controls, and the tool reads the folder each copy ended up in.

MailReach's version has you send the email yourself to the full list of seed inboxes. MailReach says this is more reliable than tools where you send to one address that forwards the message.

MailReach also calls it a spam checker and an email deliverability test on different pages. If you want the general concept without the brand, our guide to the inbox placement test covers how seed lists work.

What the spam checker looks at

The report combines three kinds of checks.

1. Inbox placement

For each seed mailbox and each provider, the report shows whether your email landed in the inbox, in spam, in a categories or promotions tab, or went missing. This is the part a content-only checker cannot give you.

2. Content

MailReach lists these content checks:

• Spam words
• Links, including insecure or broken ones
• Attachments
• Images and image-to-text ratio
• Tracking pixels
• HTML code and its complexity

For a quick wording pass before you spend a test, our free spam word checker flags risky phrases in your copy.

3. Setup and authentication

The test also reads your sending setup:

• SPF, DKIM and DMARC
• MX records and reverse DNS
• Domain age
• Whether your domain or sending IP is on a blacklist
• Blacklist hits on the links in your email

The output is a score, placement by mailbox and prioritized recommendations. MailReach says a CSV export of the seed list is available.

The seed list and providers

MailReach says the test uses 30+ different mailboxes. The providers named on its pages are Google, Microsoft and Yahoo, and its blog lists Google Workspace, Office 365, Gmail, Outlook and Yahoo.

Its API docs describe four seed list variants that can be rotated, with entries tagged as Gmail or Outlook. The exact number of inboxes per list is not stated there.

Two limits follow from that. The list is centered on the big three providers, and coverage of regional providers is not documented. MailReach's own blog says a competitor, GlockApps, covers more regional providers.

How to run a free MailReach spam test

These are the steps MailReach documents on its spam test page. We have not added any of our own.

1. Paste the code. MailReach gives you a code. Paste it anywhere in the body of your email.
2. Copy the seed list and send. Copy the list of MailReach inboxes, choosing the separator your tool needs (comma, semicolon or line break). Send your email to all of them from your real sending tool.
3. Get your score. Click "Get your score" to see the score, the placement per mailbox and the recommendations.
4. Fix and re-test. Fix what the report flags and re-test until the score improves.

You can open MailReach's free spam test and follow those steps without a credit card.

Three things MailReach says to get right

• Test the real thing. Send the test from the same sending tool, domain and content as the real campaign. A test from a different mailbox tells you about that mailbox.
• Send to the whole list. The score is built from where each copy lands, so skipping addresses weakens the result.
• Re-test on change. MailReach says you do not need a separate test per country. You do need a new test when content, links, images or the sending setup change.

How to read the MailReach score

Web score out of 10, API score from 0 to 100

MailReach's free tool describes the score out of 10; its API returns a 0 to 100 score. The web pages say 10 out of 10 means perfect deliverability for the tested email and setup.

The API docs add two audience scores alongside the overall one: one for professional inboxes and one for personal inboxes. MailReach does not document how any of these scores are calculated, so we will not guess.

Pick the audience that matches your list

Scoring can be set to the audience you target:

• Professional: Google Workspace and Microsoft 365
• Personal: Gmail.com, Outlook.com and Hotmail
• All: both groups

This matters more than it looks. MailReach says professional inboxes can show 100% inbox placement while personal inboxes still filter the same email to spam. If you sell to businesses, judge the test on the professional view.

A perfect score is not always possible

MailReach says 10 out of 10 is not always achievable for some types of email. Treat the score as a way to compare versions of your own email, not as a pass mark.

The placement by provider tells you where to look next, for example a result that is clean at Google and poor at Microsoft.

When every check is green but the score is low

MailReach gives three likely causes: your sending reputation, spam words the checker did not detect, or the sending tool itself (its IP or tracking domain).

Its suggested check is simple. Re-test with a short, two-sentence plain email sent without a sending tool. If that lands well, the problem is in your content or your tool, not your domain.

Free vs paid spam tests

Paid credits come two ways. Every MailReach warmup plan includes at least 20 credits, and the standalone Spam Tester sells credits by monthly plan or pay as you go.

On price, 200 credits at $210 a month works out to $1.05 per test. The entry price for the standalone tester conflicts across MailReach's own blog posts (between $15 and $19.50 a month), so check the slider. Our MailReach pricing guide has the full credit math.

Limits and what is not documented

• Free cap: 3 tests per 24 hours.
• Failed tests: the API docs say a credit is not charged if the test fails to collect results.
• Stored emails: MailReach stores the test emails to generate reports.
• Reputation: MailReach says the test does not harm sender reputation.
• B2B lean: MailReach says it works best for B2B cold email and has fewer personal inboxes in its network.

We could not confirm these as of November 2026:

• The exact number of inboxes in each seed list
• The full provider list beyond Google, Microsoft and Yahoo
• Frequency options for automated tests
• Whether each automated run uses one credit
• Credit expiry and rollover
• Numeric API rate limits

Automated tests and the API

On paid plans, MailReach can run tests for you at a chosen frequency and send the result to Slack or a webhook. It says automated tests work with any provider that supports SMTP, because you connect the mailbox so MailReach can send the test itself.

For developers, the documented API flow has three steps:

1. Create a test with POST /spam_tests. The response includes an ID and the seed list addresses.
2. Send your email to every seed address with that ID in the body, from the same domain, IP and email service as production.
3. Poll GET /spam_tests/{public_id} every 10 to 15 seconds until completed is true.

The result includes the overall score, the audience scores, the analysis results and blacklist data for your sending IP and links. A completed scheduled test is also one of the alert events MailReach can push to Slack or a webhook.

What to fix after a bad result

Work in this order. It follows MailReach's own help center guidance for diagnosing spam placement.

Step 1: fix anything red in setup

Missing or failing SPF, DKIM or DMARC, a blacklisted domain or IP, and broken reverse DNS come first. No copy change will outweigh a broken setup. Our guide to cold email infrastructure covers the DNS records.

Step 2: run a baseline and an "innocent" email

Run one test with your real content and conditions. Then run a second with a plain text email: neutral subject, no links, no signature, no tracking.

If the plain email lands in the inbox and the real one does not, the cause is in your content or tracking. If the plain email also lands in spam, MailReach says to suspect the sending IP, the sending setup or a list that leans heavily toward consumer inboxes.

Step 3: change one thing at a time

Test variations to isolate the cause: no tracking, no links, different wording, no images. One change per test costs more credits, but it tells you what actually moved the result.

MailReach's help center says that in 80% of cases where a sender with a high reputation score still lands in spam, the cause is links and tracking without a custom tracking domain. That is MailReach's claim, with no published data behind it. Its recommendation is a custom tracking domain that matches the sending domain, and no shortened URLs.

Step 4: look at sending behavior

If tests are clean but campaigns still struggle, the test is not the problem. MailReach's guidance for a spam spike is to reduce or pause sending, keep to no more than 100 cold emails a day per mailbox, limit follow-ups to 2, keep bounces under 5% and include a clear unsubscribe link.

A seed test does not see complaints from real recipients, so list quality matters as much as the score. For how warmup and testing fit together, see our guide to mailbox warmup and inbox placement.

A short fix checklist

• [ ] SPF, DKIM and DMARC all pass
• [ ] Domain and sending IP are not blacklisted
• [ ] Plain two-sentence email tested as a control
• [ ] Custom tracking domain set, or tracking turned off
• [ ] No shortened or broken links
• [ ] Images and attachments removed or reduced
• [ ] Spam words rewritten
• [ ] Audience view matches your real list
• [ ] Re-tested after each change

How often to test

MailReach's stated rule is to re-test whenever content, links, images or the sending setup change. For most cold email teams that means a test before each new campaign and after any change of domain, mailbox or sending tool.

Teams that want ongoing monitoring can use the automated tests. Our guide to the full email deliverability test stack shows where placement tests sit next to authentication and blacklist checks.

How it compares with other testers

Two alternatives come up most often. Details are from each vendor's own site as of November 2026.

Mail-Tester also scores out of 10 and also allows 3 free tests per 24 hours. The difference is the method: you send to one generated address and get a content and configuration score, not placement across a list of provider inboxes.

GlockApps is a dedicated placement tester with 2 free credits and paid plans from $59 a month for 360 spam test credits. It has no warmup listed on its pricing page, and MailReach's own blog says it covers more regional providers.

MailReach's place between them is a multi-provider seed test that comes bundled with warmup. The full MailReach review weighs that against its limits.

Who should use the MailReach spam test

Rather not build the list yourself?

A clean test only tells you the email can reach the inbox. Someone still has to build the list and run the sending every week.

Nerdy Joe is owned by Agency Growth Partners (AGP), and AGP builds verified lists and runs outbound for agencies. If you would rather hand that off, book a call with David.

Bottom line on the MailReach spam test

The MailReach spam test is a useful free check for B2B senders: paste a code, send to the seed list, and read placement by provider along with content and setup issues. Remember the two scales (out of 10 on the web, 0 to 100 in the API), choose the audience that matches your list, and treat the score as a comparison tool.

The free limit of 3 tests per 24 hours is enough to start, so run a free MailReach spam test on your next campaign. If you want tests alongside warmup, MailReach's warmup plans include at least 20 credits, and the MailReach review covers the rest of the product.

Sources

• MailReach email spam test
• MailReach email spam checker tool
• MailReach email deliverability test
• MailReach pricing
• MailReach Spam Test API
• MailReach API docs: spam test
• MailReach API reference
• MailReach blog: email spam test tools
• MailReach blog: Folderly pricing
• MailReach help: why you can still land in spam with a high reputation score
• MailReach help: fixing a spam spike or reputation score drop
• MailReach for deliverability consultants
• Mail-Tester
• GlockApps pricing