JWT Decoder

Overview

Important: This API only decodes tokens and does NOT verify signatures. Not suitable for security validation or production authentication.

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 -X POST https://api.apiverve.com/v1/jwtdecoder \
  -H "x-api-key: your_api_key_here" \
  -H "Content-Type: application/json" \
  -d '{
  "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c"
}'

const res = await fetch('https://api.apiverve.com/v1/jwtdecoder', {
  method: 'POST',
  headers: {
    'x-api-key': 'your_api_key_here',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
  "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c"
}),
});

if (!res.ok) throw new Error(`${res.status} ${await res.text()}`);

const { data } = await res.json();
console.log(data);

import requests

res = requests.post(
    "https://api.apiverve.com/v1/jwtdecoder",
    headers={"x-api-key": "your_api_key_here"},
    json={
    "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c"
},
    timeout=15,
)
res.raise_for_status()

print(res.json()["data"])

package main

import (
	"fmt"
	"io"
	"net/http"
	"strings"
)

func main() {
	body := strings.NewReader(`{
  "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c"
}`)
	req, _ := http.NewRequest("POST", "https://api.apiverve.com/v1/jwtdecoder", body)
	req.Header.Set("Content-Type", "application/json")
	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.

Parameters

Sent as JSON in the request body. Premium parameters are accepted on every plan but only take effect on plans that include them.

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": {
    "header": {
      "alg": "HS256",
      "typ": "JWT"
    },
    "payload": {
      "sub": "1234567890",
      "name": "John Doe",
      "iat": 1516239022
    },
    "signature": "SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c",
    "isExpired": false,
    "expiresAt": null,
    "issuedAt": "2018-01-18T01:30:22.000Z",
    "tokenAge": "2557 days",
    "algorithm": "HS256",
    "expiresIn": null,
    "notYetValid": false,
    "securityAnalysis": {
      "isUnsecured": false,
      "hasExpiration": false,
      "isLongLived": false,
      "issues": [
        "Token has no expiration (exp) claim — it never expires"
      ]
    },
    "warning": "This API only decodes JWT tokens. It does NOT verify signatures. Do not use for security validation."
  }
}

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.

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.

Use cases

Token Debugging

Debug and inspect JWT tokens during development to view header and payload contents

Token Analysis

Analyze token structure and claims without performing cryptographic verification

Expiration Check

Check token expiration status and view expiration timestamps

Token Inspection

Inspect token contents for troubleshooting authentication issues

Other ways to use JWT Decoder

Set up JWT Decoder on APIVerve, or reach the same source a different way. Your APIVerve account and credits work on all of them — one key, one balance.

Related

More in Data Conversion: