Overview
This tool inspects the DKIM record by performing DNS lookups for common selectors. It validates the syntax, surfaces the public-key length in bits, flags testing mode, and derives a composite email-signing posture score so you can tell at a glance whether a domain's DKIM key actually protects its mail.
Endpoint
One host, one path per API. The block below shows this call in four languages; every one of them is the same HTTP request. Making requests covers the timeouts, retries and parameter rules that apply to all of them. The SDKs wrap the same call in a typed client.
curl "https://api.apiverve.com/v1/dkimvalidator?domain=google.com&selector=google" \
-H "x-api-key: your_api_key_here"const res = await fetch('https://api.apiverve.com/v1/dkimvalidator?domain=google.com&selector=google', {
headers: { 'x-api-key': 'your_api_key_here' },
});
if (!res.ok) throw new Error(`${res.status} ${await res.text()}`);
const { data } = await res.json();
console.log(data);import requests
res = requests.get(
"https://api.apiverve.com/v1/dkimvalidator?domain=google.com&selector=google",
headers={"x-api-key": "your_api_key_here"},
timeout=15,
)
res.raise_for_status()
print(res.json()["data"])package main
import (
"fmt"
"io"
"net/http"
)
func main() {
req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/dkimvalidator?domain=google.com&selector=google", nil)
req.Header.Set("x-api-key", "your_api_key_here")
res, err := http.DefaultClient.Do(req)
if err != nil {
panic(err)
}
defer res.Body.Close()
out, _ := io.ReadAll(res.Body)
fmt.Println(string(out))
}Replace your_api_key_here with the key from your dashboard. When the inputs arrive as a list rather than one at a time, batch requests run up to 200 of them through this same API in a single call.
Authentication
Send your key in the x-api-key header. That is the only auth step — there is no token exchange and no per-endpoint scope to configure. Authentication covers creating, rotating and revoking keys.
A 401 means the key is missing, invalid or expired. A 403 means the key is valid but not permitted here — blocked by a key restriction or an IP allow-list. Running out of credits is a 429.
Parameters
Sent in the query string. Premium parameters are accepted on every plan but only take effect on plans that include them.
| Parameter | Type | Description |
|---|---|---|
domainRequired | string | The domain to validate the DKIM record for domain |
selectorOptional | string | The DKIM selector to look up (the label before ._domainkey). When omitted, a list of common selectors is tried |
Response
Every API returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape. Response format covers the envelope, the other output formats and how premium fields are withheld.
{
"status": "ok",
"error": null,
"data": {
"selector": "20230601",
"host": "google.com",
"dkim_host": "20230601._domainkey.google.com",
"cname_target": null,
"has_dkim_record": true,
"dkim_record": "v=DKIM1; k=rsa; p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA4zd3nfUoLHWFbfoPZzAb8bvjsFIIFsNypweLuPe4M+vAP1YxObFxRnpvLYz7Z+bORKLber5aGmgFF9iaufsH1z0+aw8Qex7uDaafzWoJOM/6lAS5iI0JggZiUkqNpRQLL7H6E7HcvOMC61nJcO4r0PwLDZKwEaCs8gUHiqRn/SS3wqEZX29v/VOUVcI4BjaOz",
"dkim_records_count": 1,
"version": "DKIM1",
"key_type": "rsa",
"key_bits": 1416,
"is_test_mode": false,
"issues_found": [
{
"code": "WEAK_PUBLIC_KEY_BITS",
"type": "warning",
"message": "Public key uses weak 1416 bits"
}
],
"valid": true,
"risk_score": 25,
"risk_level": "medium"
}
}Response fields
Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.
| Field | Type | Example | Description |
|---|---|---|---|
selector | string | "20230601" | DKIM selector used for DNS record lookup |
host | string | "google.com" | Domain name being validated |
dkim_host | string | "20230601._domainkey.google.com" | Full DKIM DNS record hostname with selector |
cname_target | object | null | CNAME target if present in DNS record |
has_dkim_record | boolean | true | Whether DKIM record exists in domain DNS |
dkim_record | string | "v=DKIM1; k=rsa; p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA4zd3nfUoLHWFbfoPZzAb8bvjsFIIFsNypweLuPe4M+vAP1YxObFxRnpvLYz7Z+bORKLber5aGmgFF9iaufsH1z0+aw8Qex7uDaafzWoJOM/6lAS5iI0JggZiUkqNpRQLL7H6E7HcvOMC61nJcO4r0PwLDZKwEaCs8gUHiqRn/SS3wqEZX29v/VOUVcI4BjaOz" | Complete DKIM record value and public key |
dkim_records_count | number | 1 | Number of DKIM records found for domain |
version | string | "DKIM1" | DKIM protocol version from record |
key_type | string | "rsa" | Public key algorithm type used |
key_bits | number | 1416 | Length of the DKIM public key in bits. 2048 or higher is the current recommendation; below 1024 is dangerously weak. 0 indicates a revoked key (empty p= value), and null means no decodable key is present |
is_test_mode | boolean | false | Whether the record sets t=y (testing mode). In testing mode receivers are told to treat mail as if DKIM were not deployed, so signatures carry no enforcement weight |
issues_foundPremium | array[1] | Array of detected issues with DKIM configuration | |
codePremium | string | "WEAK_PUBLIC_KEY_BITS" | Error code identifying the specific issue |
typePremium | string | "warning" | Severity level of the issue |
messagePremium | string | "Public key uses weak 1416 bits" | Human-readable description of the issue |
valid | boolean | true | Overall DKIM record validity status |
risk_scorePremium | number | 25 | Composite 0-100 email-signing weakness score derived from the key length, testing mode and hash algorithm — higher means the deployed DKIM key offers less real protection (a revoked or sub-1024-bit key scores high; a 2048-bit enforced key scores low) |
risk_levelPremium | string | "medium" | Risk band derived from the score: low, medium or high |
Errors
Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change. Error handling covers the full status list and which of them are worth retrying.
| Status | Meaning | What to do |
|---|---|---|
400 | Input was rejected | Read error; it names the parameter. |
401 | Key missing or invalid | Check the header name and the key value. |
403 | Key valid, but not permitted | A key restriction or IP allow-list; see key scoping. |
429 | Rate limited, or out of credits | Read error to tell them apart; see rate limits. |
Other ways to use DKIM Validator
Set up DKIM Validator on APIVerve, or reach the same source a different way. Your APIVerve account and credits work on all of them — one key, one balance.
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