SPF Checker Tool
Check and Fix Your SPF Records in Seconds
Our free SPF checker tool is the easiest way to ensure that your SPF records are correct and up-to-date.
SPF Checker Tool
SPF Record Checker
Use this tool to lookup and validate your SPF record.
SPF Status
Record Checks
| Valid SPF record | |
| Failure Mode | |
| DNS Lookups below 10 | /10 |
| Void Lookups below 2 | /2 |
| Error Details | |
| Warning |
| Tag | Value | Description |
|---|---|---|
| v | v = spf1 Record version | |
| +ip4 | Allow the listed IPv4 addresses | |
| +ip6 | Allow the listed IPv6 addresses | |
| +include | Check the SPF record of the listed domain for a matching IP address | |
| +a | Allow the IP addresses listed in the domain’s A record | |
| +mx | Allow the IP addresses of the domain’s MX hosts | |
| +ptr | Allow the IP addresses of the domain’s PTR hosts | |
| +exist | SPF passes if an A record lookup of the listed domain returns a valid result | |
| +redirected | Replace the current SPF record with that of the listed domain | |
| -/~/? | Apply a hardfail/softail/neutral result if no other mechanisms match |
Any text as spf content
This is any error
What is an SPF checker?
Our SPF checker is a tool that aids in verifying a domain’s SPF records is known as an SPF (Sender Policy Framework) record checker. SPF is an email authentication protocol that enables domain owners to declare which mail servers are permitted to send emails on their domain’s behalf, hence assisting in the prevention of email spoofing and phishing.
How SPF Checker Works
An SPF checker validates a domain’s SPF record, which specifies authorized mail servers for sending emails on behalf of the domain. The SPF record checker retrieves the domain’s SPF record, parses its rules, gathers the sender’s IP address, evaluates it against the record, and determines the result as pass, fail, softfail, neutral, or SPF permerror.
An SPF lookup with our tool performs the following functions:
Checks the existence of your published SPF recordDetects Multiple SPF LookupsEvaluates SPF Record ValidityValidates IP Addresses and Domains
1. Checks the existence of your published SPF record
Our SPF check tool will evaluate whether you have an existing SPF record published on your DNS. It fetches the SPF record from the DNS of the domain you want to check and subsequently parses the contents of the SPF record to understand the rules and mechanisms defined within it. These mechanisms specify which IP addresses and mail servers are allowed to send emails on behalf of the domain.
To find the existence of your DNS record, our SPF record check tool:
Performs an SPF DNS query
The SPF checker tool starts a DNS lookup for the target domain. To query the domain’s associated DNS records, “TXT” is appended to the domain name.
Initiates SPF Record Retrieval
The DNS server will respond with the SPF record as a text (TXT) record if the domain has an SPF record. The “v=spf1” declaration is often followed by a number of mechanisms, qualifiers, and perhaps modifiers in an SPF record.
2. Detects Multiple SPF Lookups
Our SPF checker tool can detect the SPF lookup limit exceeding by monitoring the number of DNS queries made during the SPF record validation process. If it does, it triggers a limit exceeding warning or error.
Here’s why detecting the SPF lookup limit exceeding is useful:
Preventing SPF Record Oversights
SPF records have a default lookup limit (currently 10) to prevent excessive DNS queries during SPF record validation. Exceeding this limit can lead to incomplete SPF record processing, potentially allowing unauthorized senders to pass authentication checks. By detecting limit exceeding, our tool ensures that the SPF record is not overlooked, and all relevant mechanisms are considered.
Security and Spoofing Mitigation
Our SPF lookup tool helps ensure that SPF records are correctly configured and that all authorized sending servers are accounted for. This enhances security by reducing the risk of spoofed emails.
Compliance with Standards
The SPF record lookup tool ensures that the sending domain’s SPF record complies with this standard. Non-compliance might lead to emails being treated with suspicion or rejected by recipient servers.
Performance Optimization
By validating the DNS query limit, the tool helps optimize the performance of the email authentication process and minimizes the impact on DNS infrastructure.
Configuration Feedback
If the SPF validator tool detects a limit exceeding issue, it can provide feedback to the domain owner or administrator. This feedback can guide them in adjusting their SPF record to stay within the lookup limit
3. Evaluates SPF Record Validity
Our SPF checker tool evaluates the validity of an SPF record by checking various aspects of the record’s syntax and content.
This includes:
Validation of Character Set
The SPF record lookup tool verifies that the characters used in the SPF record fall within the permitted character set specified in the SPF standard (RFC 7208). A syntax error can be raised for any use of unsupported special characters or incorrect characters.
Length Restrictions
SPF records are limited to a maximum of 255 characters. The tool verifies that the length of the retrieved SPF record does not go over this cap. Longer records need to be shortened and may be flagged as mistakes.
Mechanism and Modifier Syntax
The tool parses the SPF record and analyses each mechanism and modifier’s syntax. It makes sure they follow the SPF record syntax standards by checking for proper usage and structure. For instance:
- Mechanisms with the letters “a,” “mx,” “ip4”, and “include” should be formatted properly.
- The terms “redirect” and “exp” should relate to legitimate domains.
4. Validates IP Addresses and Domains
Our SPF test tool verifies that IP addresses and domain names specified within mechanisms are correctly formatted and resolved to valid destinations. For example, if an “include” mechanism points to another domain, the SPF lookup tool also verifies whether that domain has a valid SPF record.
IP Address Examination
Each IP address listed in the SPF record is examined by our SPF tester tool to make sure it is structured correctly. For IPv4 addresses, the format should be “ip4:192.168.1.1,” and for IPv6 addresses, “ip6:2001:0db8::1.
Aligned with Domain Naming Formats
The tool ensures that domain names supplied in tags like “a,” “mx,” “include,” and “ptr” are properly formatted and adhere to domain naming conventions.
Quick Feedback on Error Fixes
To assist domain managers in fixing the SPF record, the tool may give feedback or error messages if it runs into syntax errors or problems with IP addresses or domains. This in turn ensures that the SPF record is accurately configured by the domain owner, and permitted senders are correctly authorized during the authentication process.
