Check SPF, DKIM, DMARC, blocklists, reverse DNS and email headers against Gmail/Yahoo sender rules.
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Check a domain's SPF (including the 10-DNS-lookup limit), DMARC policy and reporting, DKIM keys on common selectors, and MX records. Returns problems ranked by severity with the fix for each, plus the email services the domain uses.
The domain, e.g. example.com (a URL or email address's domain also works).
Extra DKIM selectors to look for, e.g. from the s= value of a message's DKIM-Signature header.
Check a domain's SPF (including the 10-DNS-lookup limit), DMARC policy and reporting, DKIM keys on common selectors, and MX records. Returns problems ranked by severity with the fix for each, plus the email services the domain uses.
| Argument | Type | Description |
|---|---|---|
| domain* | string | The domain, e.g. example.com (a URL or email address's domain also works). |
| dkim_selectors | array | Extra DKIM selectors to look for, e.g. from the s= value of a message's DKIM-Signature header. |
{
"type": "object",
"$schema": "http://json-schema.org/draft-07/schema#",
"required": [
"domain"
],
"properties": {
"domain": {
"type": "string",
"maxLength": 253,
"minLength": 3,
"description": "The domain, e.g. example.com (a URL or email address's domain also works)."
},
"dkim_selectors": {
"type": "array",
"items": {
"type": "string",
"maxLength": 63
},
"maxItems": 10,
"description": "Extra DKIM selectors to look for, e.g. from the s= value of a message's DKIM-Signature header."
}
}
}Check a received email's headers against Gmail's and Yahoo's bulk sender requirements: SPF, DKIM and DMARC results, From domain alignment, one-click unsubscribe (and whether DKIM covers it), TLS, reverse DNS and Message-ID. Use the full headers as the recipient got them (Gmail: Show original).
| Argument | Type | Description |
|---|---|---|
| headers* | string | The raw message headers (the body may be included; it's ignored). |
{
"type": "object",
"$schema": "http://json-schema.org/draft-07/schema#",
"required": [
"headers"
],
"properties": {
"headers": {
"type": "string",
"maxLength": 200000,
"minLength": 10,
"description": "The raw message headers (the body may be included; it's ignored)."
}
}
}Check a mail server's IP: reverse DNS (PTR) and whether it resolves back to the IP, and listings on Spamhaus ZEN, Barracuda, SpamCop, PSBL, Mailspike and UCEPROTECT level 1. A refused Spamhaus query is reported as unknown, never as a listing.
| Argument | Type | Description |
|---|---|---|
| ip* | string | IPv4 or IPv6 address of the sending server. |
{
"type": "object",
"$schema": "http://json-schema.org/draft-07/schema#",
"required": [
"ip"
],
"properties": {
"ip": {
"type": "string",
"maxLength": 45,
"minLength": 2,
"description": "IPv4 or IPv6 address of the sending server."
}
}
}