URL-safe Base64 Decoder (Base64URL) – Decode JWT / URL-safe strings

Base64URL (URL-safe Base64) is commonly used in JWT and URLs. This page explains how to decode it safely and what to do about missing padding.

Try the tool:

Use the full interactive tool here: Base64 Decoder

Example

Base64URL input

SGVsbG8tX3dvcmxk

Decoded text

Hello-_world

What is Base64URL?

Base64URL is a URL-safe variant of Base64 that uses '-' and '_' instead of '+' and '/' and often omits '=' padding.

Do I need padding '=' to decode?

Some decoders require padding. You can add '=' until the length is a multiple of 4.