Base64 Encoder & Decoder

What Is a Base64 Encoder / Decoder?

A Base64 encoder/decoder transforms text into Base64 representation and converts Base64 back to readable UTF-8 text. It is commonly used in APIs, tokens, data transport, and debugging encoded payloads.

It helps validate encoded data quickly, troubleshoot API payloads, and safely convert between standard and URL-safe Base64 forms without manual errors.

How to Use the Base64 Encoder / Decoder - Step by Step

1. 1

   Paste input text

   Enter plain text or Base64 content.

2. 2

   Choose mode and alphabet

   Select encode/decode and standard or URL-safe alphabet.

3. 3

   Set advanced options

   Choose strict decoding, padding preference, and iteration count.

4. 4

   Process

   Get converted output and length metrics instantly.

Frequently Asked Questions - Base64 Encoder / Decoder

What is URL-safe Base64?

URL-safe Base64 uses - and _ instead of + and / so encoded values are safer in URLs and query strings.

Why strict decode mode?

Strict mode rejects malformed Base64 so you can catch bad input early and avoid silent corruption.

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