Base64 Decoder API

Decode Base64 encoded text back to plain text instantly for JWT token processing, email decoding, and secure data retrieval. Simple API, instant results.

✓ Used for JWT token processing

✓ RFC 4648 compliant

✓ Handles malformed input gracefully

🚀 Start Decoding for Free

✓ 100 free decodings monthly ✓ No credit card ✓ Instant setup

How to Decode Base64 to Text

Input: Base64 Encoded

SGVsbG8sIFdvcmxkIQpUaGlzIGlzIGEgc2VjcmV0IG1lc3NhZ2UuClNwZWNpYWwgY2hhcnM6IMOlw6TDtiBAIyQl

Base64 encoded text from emails, JWT tokens, or API responses that needs to be decoded back to readable format.

Output: Plain Text

Hello, World!
This is a secret message.
Special chars: åäö @#$%

Original readable text with proper Unicode support and special character handling.

API Usage Examples

Basic Text Decoding

curl -X POST https://api.t3xtr.org/api/base64-decode \
  -H "X-API-Key: YOUR_API_KEY" \
  -H "Content-Type: text/plain" \
  -d "SGVsbG8sIFdvcmxkIQ=="

# Response
Hello, World!

JWT Payload Decoding

curl -X POST https://api.t3xtr.org/api/base64-decode \
  -H "X-API-Key: YOUR_API_KEY" \
  -H "Content-Type: text/plain" \
  -d "eyJ1c2VyX2lkIjogMTIzNDUsICJleHAiOiAxNjQwOTk1MjAwfQ=="

# Response - JWT payload
{"user_id": 12345, "exp": 1640995200}

URL-Safe Base64 Decoding

curl -X POST https://api.t3xtr.org/api/base64-decode \
  -H "X-API-Key: YOUR_API_KEY" \
  -H "Content-Type: text/plain" \
  -d "SGVsbG8gV29ybGQh"

# Response
Hello World!

Common Base64 Decoding Use Cases

🔐 JWT Token Processing

Decode JWT headers and payloads to extract user information and token claims.

Perfect for: OAuth validation, API authentication, session analysis

📧 Email Processing

Decode Base64 encoded email content and attachments from MIME messages.

Perfect for: Email parsing, attachment extraction, content analysis

🌐 URL Parameter Decoding

Decode complex data that was Base64 encoded for safe URL transmission.

Perfect for: Deep link parsing, state recovery, callback processing

💾 Data Retrieval

Decode binary data stored as Base64 in databases and configuration files.

Perfect for: Database records, config parsing, file reconstruction

🔗 API Response Processing

Decode Base64 encoded payloads received from third-party APIs and webhooks.

Perfect for: Webhook processing, API integration, data parsing

📱 Mobile App Data

Decode app data that was Base64 encoded for secure transmission or storage.

Perfect for: User data recovery, cache processing, sync operations

Programming Language Examples

JavaScript/Node.js

const response = await fetch('https://api.t3xtr.org/api/base64-decode', {
  method: 'POST',
  headers: {
    'X-API-Key': 'YOUR_API_KEY',
    'Content-Type': 'text/plain'
  },
  body: 'SGVsbG8sIFdvcmxkIQ=='
});
const decoded = await response.text();

Python

import requests

response = requests.post(
    'https://api.t3xtr.org/api/base64-decode',
    headers={'X-API-Key': 'YOUR_API_KEY'},
    data='SGVsbG8sIFdvcmxkIQ=='
)
decoded = response.text

PHP

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, 'https://api.t3xtr.org/api/base64-decode');
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, 'SGVsbG8sIFdvcmxkIQ==');
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    'X-API-Key: YOUR_API_KEY'
]);
$decoded = curl_exec($ch);

Java

HttpRequest request = HttpRequest.newBuilder()
    .uri(URI.create("https://api.t3xtr.org/api/base64-decode"))
    .header("X-API-Key", "YOUR_API_KEY")
    .POST(HttpRequest.BodyPublishers.ofString("SGVsbG8sIFdvcmxkIQ=="))
    .build();
    
String decoded = client.send(request, 
    HttpResponse.BodyHandlers.ofString()).body();

Why Use T3XTR for Base64 Decoding?

🚀 Lightning Fast

Decode Base64 text in under 100ms. Perfect for real-time applications and high-frequency decoding operations.

📏 No Size Limits

Decode up to 10MB of Base64 data per request. Handle large files, documents, and data payloads.

🔒 Secure Processing

Your data is processed securely and never stored. GDPR compliant with enterprise-grade security.

🌐 RFC Compliant

Follows RFC 4648 standards for Base64 decoding. Compatible with all systems and platforms.

🛡️ Error Handling

Gracefully handles malformed Base64 input with clear error messages and validation.

🛠️ Developer Friendly

Simple REST API works with any programming language. Comprehensive documentation and examples.

Frequently Asked Questions

What happens with malformed Base64?

T3XTR handles malformed Base64 gracefully and returns clear error messages to help you identify issues with the input data.

Can I decode URL-safe Base64?

Yes! T3XTR automatically detects and handles both standard and URL-safe Base64 encoding formats.

Does it preserve Unicode characters?

Absolutely! T3XTR handles UTF-8 decoding automatically, preserving all Unicode characters and special symbols.

What's the maximum decode size?

You can decode up to 10MB of Base64 data per API request, suitable for most applications and large documents.

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