SenderCheck vs MXToolbox
MXToolbox is the broadest free lookup suite for DNS, blacklists and mail servers, the tool most sysadmins already have bookmarked. SenderCheck is narrower on purpose: it covers only email authentication (SPF, DKIM, DMARC, MX, MTA-STS, BIMI), explains each result in plain English, and watches your records continuously so you are told the day one breaks. Use MXToolbox for a one-off lookup across many record types; use SenderCheck when you want continuity and a fix, not just a reading.
Check your domain firstFree · no account
What MXToolbox does better
Breadth. MXToolbox covers far more than email authentication (blacklist monitoring, general DNS, network diagnostics), and its lookups are fast, free and familiar. For an ad-hoc check across many record types, it is hard to beat and needs no account.
How they differ
The two tools answer different questions. MXToolbox answers “what does this record say right now?” across a huge range of record types. SenderCheck answers “is my email authentication correct, what does each problem actually mean, and how do I keep it that way?”
The gap SenderCheck fills is continuity. A free lookup is a snapshot; it cannot notice that your SPF record broke three weeks ago when a vendor edited theirs. SenderCheck re-checks on a schedule and alerts you when a record changes or fails, which is the whole reason the paid tiers exist.
Side by side
| Dimension | MXToolbox | SenderCheck |
|---|---|---|
| Record types covered | Very broad: DNS, blacklists, mail, network | Email authentication only, in depth |
| Plain-English explanation of each result | Terse, technical | A written explanation and the exact fix per finding |
| Continuous monitoring & change alerts | Available, aimed at larger senders | The core of the product, priced for one small business |
| Free one-off checks | Yes, extensive | Yes, every tool |
| Needs an account to start | No | No |
Swipe sideways to see the SenderCheck column.
A highlighted cell marks the genuine edge. Where both are strong it is left even: the point is an honest read, not a scorecard.
Which to choose
Choose MXToolbox if
- You need a blacklist check, a general DNS lookup, or a network diagnostic, things SenderCheck deliberately does not do.
- You want one tab that does a bit of everything and you already know how to read the output.
- You are a network professional doing an ad-hoc investigation, not setting up ongoing protection.
Choose SenderCheck if
- You want to be told when a record breaks, not to remember to re-check it.
- You want each finding explained and the exact record to publish, not just the raw value.
- You have one or a few domains and want monitoring priced for that, not for an enterprise.
Common questions
- Is SenderCheck a good MXToolbox alternative?
- For email authentication specifically, yes: it explains each result and monitors your records continuously, which a one-off lookup does not. For blacklist checks, general DNS and network diagnostics, MXToolbox is broader and SenderCheck does not try to compete there. Many people use both.
- Does MXToolbox monitor DNS changes like SenderCheck?
- It offers monitoring, but it is positioned for larger senders and bundled into a broader delivery product. SenderCheck's monitoring is the whole point of the product and is priced for a single small business watching one to a handful of domains.
- Is SenderCheck free like MXToolbox?
- The checks are free and need no account, the same as MXToolbox. The paid tiers add continuous monitoring, change alerts and history: the continuity a free lookup cannot provide.