Mailook Review

Mailook is a free diagnostic tool that answers one question: why might your cold email be landing in spam, and what should you do about it. It runs a domain and mailbox through a blacklist scan and an authentication check, then hands back a plain-English report instead of raw DNS output. This review covers what the tool actually checks, what its "free" claim really means in practice, and where it fits next to paid deliverability infrastructure.

Verdict at a glance

What is Mailook?

Mailook checks whether a domain's sending setup is likely to hurt inbox placement. It scans IP and domain reputation against what the vendor describes as more than 100 blacklists, and inspects SPF, DKIM, and DMARC records for the kind of misconfiguration that quietly tanks deliverability — a missing DMARC policy, a broken SPF alignment, a DKIM key that doesn't match. The vendor advertises a 120-point audit behind that scan.

The differentiator from a raw DNS lookup tool is translation: instead of returning a technical pass/fail per record, Mailook is built to explain the problem and the fix in language a sales or marketing person, not a sysadmin, can act on. Reports also generate a shareable public link, which is the feature agencies get the most obvious use out of — sending a client a URL is easier than screen-sharing a terminal.

How it works

The flow is lightweight by design: sign up at app.mailook.ai, connect the domain or mailbox you want checked, and run the scan. The tool works against any email service provider — the vendor names Gmail, Outlook, Yahoo, Sendgrid, Sendinblue, Mailgun, and Amazon SES specifically — so it doesn't require routing mail through Mailook's own infrastructure. A dashboard keeps a history of past checks, which is what lets you confirm a fix actually moved the needle rather than assuming it did after making a DNS change.

There's no onboarding call, contract, or credit card involved in getting a first report, which is consistent with a tool positioned as a lightweight first stop before something more involved.

Mailook pricing (2026)

Mailook's own marketing is direct about this: the tool is free, and the site does not publish a paid tier. The one hard number is a usage cap — 50 deliverability tests per month per user on the free plan. Past that, the vendor's own pricing page says to reach out directly rather than pointing to a plan or a price.

That's worth naming plainly as the catch, since "totally free" is the headline claim: there is no visible self-serve path once you outgrow 50 tests a month, which matters for an agency running audits across many client domains, less so for a single team checking its own sending health occasionally. Whatever a scaled plan costs, it isn't public.

What we could and couldn't verify

We could verify the vendor's own claims about features and the free-tier limit directly from the Mailook site. We could not find a Trustpilot, G2, or Capterra listing for Mailook, and no meaningful Reddit discussion turned up either — no threads in r/coldemail or r/sales mentioning it by name. That's not unusual for a free single-purpose utility with a small footprint, but it does mean there is no independent sentiment to weigh the vendor's claims against: no aggregate rating, no complaint themes, no confirmation from users beyond the vendor's own site copy. Treat the feature list above as advertised, not tested by a third party.

Pros and cons

Pros

• No cost and no signup friction to get a first deliverability report
• Plain-English fix guidance, not raw DNS record dumps
• Works with any ESP — no need to route mail through Mailook
• Shareable report links suit agencies auditing client domains
• Historical tracking lets you confirm a fix actually worked

Cons

• No independent reviews found to corroborate vendor claims
• Pricing past the 50-test free cap isn't published — you have to contact sales
• A point-in-time scan, not continuous monitoring — it won't catch a blacklisting the day it happens
• No visible information on the company behind it (team, founding date) to gauge longevity

Mailook alternatives

Mailook is a diagnostic, not infrastructure — it tells you something is wrong rather than preventing the problem in the first place. Depending on which side of that line you need, the useful comparisons differ:

• GlockApps — a longer-established inbox placement and deliverability testing tool with paid tiers and a larger public track record.
• Mail-Tester — a free, single-scan tool for a quick spam-score check, narrower than Mailook's ongoing dashboard.
• ZeroBounce and NeverBounce — approach inbox placement from list quality and email verification rather than domain authentication.
• Slicey — managed, done-for-you Google and Microsoft inboxes (Microsoft from $0.49 per inbox) with a self-serve dashboard, delivered pre-warmed with deliverability monitoring and automatic domain swaps. Slicey customers also get Outfalcon, a free bundled sequencer with unlimited sending.

The choice largely comes down to whether you want to keep diagnosing your own infrastructure's problems (Mailook, GlockApps, Mail-Tester) or hand the underlying inbox and monitoring work to a provider so there's less to diagnose (Slicey).

Who should use Mailook — and who shouldn't

Good fit: teams who suspect a deliverability problem and want a fast, free, plain-English read on SPF/DKIM/DMARC and blacklist status before spending money elsewhere; agencies that want a shareable link to show a client the state of their domain.

Poor fit: teams needing continuous, real-time monitoring rather than a manual on-demand scan; agencies running audits at a volume that will blow past the 50-test cap and need clear self-serve pricing to plan around; anyone who wants third-party validation of the tool itself before relying on it, since no independent reviews currently exist.