Start with the live form
Enter a domain, URL, IP, email, or record and get a focused result without setup.
📧 SPF Record Builder
Build and validate SPF records. Visual SPF builder with include, IP, and mechanism support.
Building SPF record...
Generated SPF Record
API Endpoint
POST /v1/tools/spf/build
Interactive intelligence tool
Run the check, then ship the workflow
Use the browser tool for a fast answer, then move the same logic into scripts, monitoring, or product flows when it becomes repeatable.
Review decision-ready signals
Outputs highlight statuses, risks, records, and next actions instead of raw provider noise.
Automate the winning workflow
Use the request and response examples to turn a one-off check into an API call or recipe.
Used by people at amazing companies
What this tool helps you decide
Each page is shaped around a practical operational question, not just a raw lookup.
See the current DNS, registration, security, pricing, or reputation evidence.
Compare the result with related checks so the next move is easier to trust.
Copy examples, open linked tools, or move into API documentation when you need scale.
Trust signals before you integrate
Transparent docs, authenticated requests, and visible reliability details make it easier to evaluate DomScan before you ship.
Uptime
API artifacts
OpenAPI, Swagger, Postman, CLI, SDK, and MCP links are one click away.
API keys
Protected access
Authenticated endpoints use API keys with clear credit costs before you call them.
Free allowance
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Active
Example Request
Start from the curl and HTTP samples, then map the parameters into your application code.
Key Features
Default Policy
Choose soft fail, hard fail, or neutral for the ending mechanism.
Include domains (one per line)
Add third-party mail providers one line at a time.
DNS Lookups
Track DNS lookups so the SPF record stays within protocol limits.
Example Request
{
"all": "softfail",
"include": ["_spf.google.com"],
"ip4": ["203.0.113.0/24"]
}Example Response
{
"record": "v=spf1 include:_spf.google.com ip4:203.0.113.0/24 ~all",
"dns_lookups": 3
}Built from the same API surface
The browser experience previews DomScan's structured endpoints, so teams can validate a use case before writing code.
Frequently Asked Questions
What counts toward the 10 DNS lookup limit?
Each include, redirect, a, mx, ptr, exists, and ip mechanism can contribute to lookup usage. Keep the final record under the SPF limit.
Why is ~all usually recommended?
Soft fail is a safer default while you are testing. You can move to -all once you are confident all sending sources are covered.
Can I add multiple sending services?
Yes. Add each vendor as an include and add direct IP ranges only when the sender requires it.