TroubleshootingDeveloper troubleshooting fixes

Base64 invalid length fix

Fix Base64 invalid length errors by checking padding, URL-safe alphabets, whitespace, and binary/text assumptions.

Use this page when a Base64 decoder rejects input or produces unreadable output during API, log, or token debugging.

Invalid length often means missing padding or accidental truncation.

URL-safe Base64 replaces + and / with - and _, so use the right alphabet before decoding.

A successful decode can still be binary data, compressed data, or text in a different encoding.

Steps

1. Remove transport noise
Trim quotes, whitespace, line breaks, and copied prompt characters before retrying the decode.
Base64 Encode/Decode
2. Check the alphabet
If the value contains - or _, treat it as URL-safe Base64 or convert those characters before decoding.
URL Encode/Decode
3. Restore padding
If length modulo 4 is 2, add ==; if it is 3, add =. If it is 1, the value is probably truncated.
Base64 Encode/Decode
4. Confirm whether the result is text
Decoded bytes may be binary, compressed, encrypted, or text in a different encoding.

Base64 encodes bytes in groups that commonly end with padding. Some transports remove padding, wrap lines, or switch to the URL-safe alphabet.

Do not keep adding random characters until the decoder accepts the string. That can produce a different byte stream and hide the upstream problem.

Open the focused tools directly. These links use the same registry data as search and sitemap generation.

Base64 Encode/Decode

Encode text to Base64 format or decode it back to a readable string.

URL Encode/Decode

Encode text for safe URL transmission or decode it back to readable string.

JWT Decoder

Decode JSON Web Tokens instantly. Never sends your token to any server.

Hash Generator

Instantly generate MD5, SHA-1, SHA-256, and SHA-512 hashes from text.

Base64 values can contain tokens, file fragments, or logs. Keep raw input out of persistent storage and shared diagnostics.

Add padding only to make the length divisible by 4: == for remainder 2, = for remainder 3. A remainder of 1 usually means truncation.

The decoded bytes may be binary, compressed, encrypted, or text using a different character encoding.

Steps

1. Remove transport noise

Trim quotes, whitespace, line breaks, and copied prompt characters before retrying the decode.

2. Check the alphabet

If the value contains - or _, treat it as URL-safe Base64 or convert those characters before decoding.

3. Restore padding

If length modulo 4 is 2, add ==; if it is 3, add =. If it is 1, the value is probably truncated.

4. Confirm whether the result is text

Decoded bytes may be binary, compressed, encrypted, or text in a different encoding.