Your SPF record decides whether mail servers trust the emails you send. It's a TXT record in your DNS that lists every server allowed to send email for your domain. When it's missing or broken, your emails can land in spam or get rejected, and you often won't know until a customer says they never got your message.
SPF records break more easily than most people think. A second record added during a tool setup, a typo in an include, or going over the 10 DNS lookup limit can all cause failures. And since Gmail, Yahoo, and Microsoft now require authentication from bulk senders, these errors hurt more than they used to.
The fix starts with a good SPF checker. Below are seven tools worth knowing, what each one does well, and when to use it.
What to Look for in an SPF Checker
Before you pick a tool, know what a useful check should tell you:
- Whether an SPF record exists, and whether there's only one
- Any syntax errors in the record
- How many DNS lookups the record uses (the limit is 10)
- Which services and IP addresses are authorized
- Whether the "all" setting is safe
The best tools don't just show your record. They explain what's wrong and help you fix it.
1. EasyDMARC SPF Checker
The EasyDMARC spf checker is the most complete free option on this list and the easiest to read. You enter your domain, run the check, and get your full SPF record with a clear breakdown of what passes and what needs attention.
Its strongest feature is the lookup tree. Instead of showing only the raw record, it expands every include so you can see each sending source and how many DNS lookups it adds. This is the fastest way to find out why you're over the 10 lookup limit, which is one of the most common reasons SPF fails.
What it checks:
- Whether the SPF record exists
- Syntax errors
- Invalid or missing IP addresses
- The 10 DNS lookup limit
- Sending sources behind each include
If the check finds a problem, you can build a corrected record with EasyDMARC's SPF Record Generator and run the check again to confirm the fix. Because SPF is only one part of email authentication, the same site also has DKIM and DMARC checkers, so you can review your whole setup in one place.
Best for: Anyone who wants a clear, complete SPF check with a lookup count and next steps, whether you're a marketer or an IT admin.
2. MxToolbox SPF Record Lookup
MxToolbox is one of the oldest DNS tools around, and many IT teams know it well. Its SPF lookup shows your record, lists each mechanism, and runs a set of pass or fail tests, including a lookup count.
The benefit is that it sits alongside MX lookups, blacklist checks, and other DNS tools, so you can check several things in one visit. The results page can feel crowded, though, and some deeper features require a paid plan.
Best for: Admins who already use MxToolbox for DNS and blacklist checks.
3. dmarcian SPF Surveyor
SPF Surveyor turns your record into an expanded view where each include opens to show the IPs and nested records behind it, along with the total lookup count.
This makes it helpful when you inherit a domain with a long, messy record and need to understand where each entry came from before cleaning it up.
Best for: Tracing and cleaning up old records with many nested includes.
4. Kitterman SPF Validator
Kitterman's tool is simple and has been a favorite of email admins for years. It does two things many tools skip: it validates an SPF record before you publish it, and it tests whether a specific IP address would pass for a domain.
That makes it useful when you're planning a change. Paste your new record, check the syntax, and test it against your mail server's IP before you touch DNS.
Best for: Testing a draft record before it goes live.
5. Google Admin Toolbox Check MX
If your company uses Google Workspace, this free tool from Google checks your domain's DNS setup, including SPF, against what Workspace needs. It flags missing or wrong settings in plain terms.
It won't show a detailed lookup tree, but it's a solid check straight from your email provider.
Best for: Google Workspace users confirming their setup.
6. Vamsoft SPF Policy Tester
Vamsoft's tester lets you enter a domain, a sender address, and an IP, then walks through how the SPF check would be evaluated step by step. You see which mechanism matched and what the final result would be.
When one service keeps failing SPF, this is a good way to see exactly where the check breaks.
Best for: Debugging why a specific sender or IP fails.
7. Mail-Tester
Mail-Tester works differently from the others. Instead of looking up your DNS, you send a real email to an address it gives you. It then scores the message and shows whether SPF, DKIM, and DMARC passed, along with other issues that can push you toward spam.
This is useful because it tests an actual email from a real sending service, not just the record in DNS.
Best for: Checking how a real email from a specific platform performs.
How to Choose the Right Tool
You don't need all seven. Here's a simple way to decide:
- For a full check with clear results, start with EasyDMARC
- To test a record before publishing, use Kitterman
- To debug one failing sender, use Vamsoft or Mail-Tester
- For Google Workspace setup, use Google Admin Toolbox
Most teams use one main checker for regular reviews and a second tool when they need to troubleshoot something specific.
Common SPF Errors These Tools Catch
Whichever tool you use, watch for these issues:
- Two SPF records on one domain. Only one is allowed. Merge them into a single record.
- More than 10 DNS lookups. Remove services you no longer use, or flatten the record.
- Using "+all". This lets any server send as your domain. Use "~all" or "-all" instead.
- Includes you don't need. Some platforms use their own return-path domain, so their include adds lookups without helping.
- Missing senders. Every tool that sends email with your domain, such as your CRM or help desk, needs to be listed.
Final Thoughts
A broken SPF record can quietly stop your emails from reaching people. Checking it takes less than a minute, and doing it after every new email tool you add will save you from harder problems later.
Start with a full check, fix what it finds, and check again. Once your SPF record passes, review DKIM and DMARC too, since the three work together to protect your domain and get your emails delivered.
