Best Free SPF Checker Tools in 2026: Detailed Comparison

The best free SPF checker tool depends on what you need: if you want recursive tree visualization with exact lookup counts per mechanism, use AutoSPF’s SPF Checker. If you want the broadest multi-protocol feature set, use MxToolbox. If you want a graphical SPF map, use dmarcian. All of them query the same live DNS data — the difference is in how they parse, visualize, and flag issues.

We tested all 8 tools below against the same domain to compare results. Every tool listed here is genuinely free for basic SPF checking — no credit card, no trial, no signup required.

Per RFC 7208, SPF evaluation is capped at 10 DNS mechanism lookups and 2 void lookups. Every tool below checks against these limits, but they differ in how clearly they report violations.

What Does AutoSPF’s Free SPF Checker Do?

AutoSPF SPF Checker — built by AutoSPF (the company behind this site).

• Recursive tree visualization — expands every include, redirect, and nested mechanism into a visual tree showing exactly where each DNS lookup is consumed
• Per-mechanism lookup counting — shows the lookup cost of each individual mechanism path, not just the total. If include:sendgrid.net costs 5 lookups, you see which 5 nested records contribute
• Void lookup detection — flags mechanisms that resolve to empty DNS responses (counted toward the RFC 7208 2-void limit)
• Macro detection — identifies SPF macro syntax (%{i}, %{s}, %{d}) used for dynamic resolution
• Auto-run from URL — supports ?domain=example.com for embedding in dashboards and campaigns
• Rate limited — 30 requests per minute per IP to prevent abuse

Best for: Enterprise teams with complex, multi-vendor SPF records who need per-mechanism lookup analysis, plus enterprise features (SLAs, SSO/SAML, RBAC, audit logs, DNS rollback) on the management side.

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What Does MxToolbox SPF Checker Do?

MxToolbox SPF Check — the industry standard for DNS diagnostics.

• Checks SPF, DKIM, DMARC, MX, blacklist, and 20+ other record types from one interface
• Shows the raw SPF record with syntax highlighting
• Counts DNS lookups and flags if over 10
• Reports on deprecated mechanisms (ptr) and syntax errors
• Offers a paid “Delivery Center” tier with SPF flattening and monitoring

Best for: IT administrators who need a Swiss Army knife for all DNS diagnostics, not just SPF.

What Does dmarcian SPF Surveyor Do?

dmarcian SPF Surveyor — a graphical SPF visualization tool.

• Renders the SPF record as a visual flow diagram showing the evaluation path
• Color-codes mechanisms by type (include, ip4, a, mx)
• Identifies the source of each authorized IP range (vendor attribution)
• Shows total lookup count with clear pass/fail indicator

Best for: Visual learners who prefer a diagram over a text-based tree. Excellent for presentations and stakeholder communication.

What Does EasyDMARC SPF Lookup Do?

EasyDMARC SPF Lookup — a clean SPF analyzer with sender identification.

• Shows the SPF lookup tree with expandable nodes
• Identifies sending sources (Google, Microsoft, SendGrid, etc.) by name
• Reports lookup count and flags limit violations
• Offers guided remediation suggestions for common errors

Best for: Teams that are new to SPF and want contextual explanations alongside the raw data.

What Does DMARCLY SPF Checker Do?

DMARCLY SPF Record Checker — a straightforward checker with a clean interface.

• Shows the raw record, parsed mechanisms, and total lookup count
• Flags syntax errors and deprecated mechanisms
• Warns if the record exceeds the 10-lookup limit
• Upsells their “Safe SPF” flattening service for records that exceed the limit

Best for: Quick, no-frills SPF checks when you just need to know if the record is valid and under the limit.

What Does PowerDMARC SPF Checker Do?

PowerDMARC SPF Record Lookup — part of a broader DMARC platform.

• Checks SPF, DMARC, DKIM, BIMI, MTA-STS, and TLS-RPT from one interface
• Shows lookup count and flags violations
• Reports on alignment issues relevant to DMARC
• Upsells their “PowerSPF” hosted flattening service

Best for: Organizations evaluating PowerDMARC’s broader platform and want to test the tool before committing.

What Does Mailtrap SPF Checker Do?

Mailtrap SPF Record Checker — developer-focused, part of Mailtrap’s email testing suite.

• Shows SPF record with parsed mechanisms
• Reports lookup count and basic validation
• Integrates with Mailtrap’s email testing sandbox
• API access available for automated testing pipelines

Best for: Development teams that use Mailtrap for email testing and want SPF checking integrated into their workflow.

What Does DNS Checker SPF Lookup Do?

DNS Checker SPF Validation — the zero-signup option.

• No account, no cookies, no tracking — just paste a domain and get results
• Shows raw SPF record from DNS
• Basic syntax validation
• Propagation checking across multiple global DNS servers

Best for: Quick one-off lookups when you don’t want to create an account or deal with upsells.

How Do These SPF Checkers Compare Side by Side?

Feature	AutoSPF	MxToolbox	dmarcian	EasyDMARC	DMARCLY	PowerDMARC	Mailtrap	DNS Checker
Lookup count	Per-mechanism	Total only	Total	Per-node	Total	Total	Total	Basic
Tree visualization	Recursive	Flat list	Flow diagram	Expandable	None	None	None	None
Void lookup detection	Yes	Yes	No	No	No	No	No	No
Macro detection	Yes	No	No	No	No	Yes	No	No
Vendor identification	Via CNAME	No	Yes	Yes	No	No	No	No
Auto-run from URL	Yes	No	No	No	No	No	No	No
Multi-protocol (DMARC/DKIM)	Separate tools	Yes	Separate	Separate	Separate	Yes	No	Yes
No signup required	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
API access	No	Paid	No	Paid	No	Paid	Paid	No
SPF flattening upsell	Yes	Yes	No	Yes	Yes	Yes	No	No

Which SPF Checker Should You Use?

• For complex records with many includes: AutoSPF — the per-mechanism lookup breakdown shows exactly which vendor is consuming your budget
• For a one-stop DNS diagnostic: MxToolbox — 20+ record types in one interface
• For visual stakeholder presentations: dmarcian — the flow diagram is unmatched for non-technical audiences
• For SPF beginners: EasyDMARC — guided explanations and sender identification help you understand what you’re looking at
• For quick checks with zero friction: DNS Checker — no account, no cookies, just results

Whichever tool you use, the underlying check is the same: fetch the TXT record at the domain apex, parse the SPF mechanisms, recursively resolve includes, count DNS lookups, and flag violations of RFC 7208. The tools differ in visualization and explanation, not in the data they retrieve.

If your record exceeds 10 lookups, no free checker tool will fix it — you need an SPF flattening or SPF macro service to resolve the includes into static IP addresses. AutoSPF automates this and re-scans vendor IP changes every 15 minutes.

Related Reading

• SPF flattening tools
• PowerDMARC alternatives
• copy-paste SPF record examples