About The Base64 Inspector

Base64 Inspector decodes Base64 input and reports byte length, a hex preview, a UTF-8 preview, and formatted JSON when the decoded text is JSON. It is useful for debugging payloads, logs, and encoded fixtures.

Inspection runs locally in your browser. Base64 is encoding, not encryption, so decoded data may contain readable secrets.

How to Inspect Base64 Online

1. Paste a Base64 or Base64URL value into the input.
2. Enable URL-safe mode when the string uses - and _.
3. Click Inspect Base64 and review the byte, text, and JSON previews.

Choosing Options Correctly

URL-safe Base64:
Turn this on for Base64URL values, common in JWTs and URL-safe tokens. Leave it off for standard Base64 using + and /.

Common Use Cases

• Inspecting encoded JSON payloads from APIs.
• Checking Base64 values found in logs.
• Debugging invalid padding or URL-safe encoding problems.

Quick FAQ

Does this decrypt data?
No. Base64 decoding only reverses an encoding. It cannot decrypt encrypted content.

Why did decoding fail?
The input may be malformed, missing padding, use URL-safe Base64, or include characters outside the Base64 alphabet.

Can it detect JSON?
If decoded bytes are valid UTF-8 JSON, the tool may format or identify it; binary data may stay unreadable.

Should I inspect secrets here?
Avoid pasting tokens, keys, or credentials unless they are test values. Base64 often hides sensitive data in plain sight.