Decode Base64 to JSON Instantly (Pretty-Print & Syntax Highlight)
Decode base64-encoded JSON payloads and pretty-print the result with syntax highlighting. Supports standard and URL-safe base64 variants.
How to Use Base64 JSON Decoder
How to Use Base64 JSON Decoder
Step 1: Paste Your Base64 String
Copy any base64-encoded JSON string and paste it into the input field. This tool accepts:
- Standard base64 (uses
+and/, may end with=padding) - URL-safe base64 (uses
-and_, no padding required) - JWT payload segments (the middle part of a JWT token)
Step 2: Instant Decode
The JSON is decoded and pretty-printed automatically as you type. No button press required.
Step 3: Inspect or Copy
Use the syntax-highlighted output to inspect the JSON structure, then click Copy JSON to grab the formatted result.
Use Cases
- Inspect JWT token payloads without pasting into external sites
- Debug base64-encoded API responses and webhook bodies
- Decode OAuth or SSO token claims
- Verify configuration objects stored as base64
Tips
- For JWTs, use only the middle segment (between the two dots)
- URL-safe base64 (no
=padding) is handled automatically - The tool preserves all JSON structure including nested objects and arrays
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