Base64 Encoder & Decoder

How to use the base64 encoder & decoder

1. Paste your text or Base64 string.
2. Pick Encode or Decode, and the URL-safe alphabet if you need it.
3. Copy the result.

About this tool

Base64 turns arbitrary bytes into 64 printable characters so they survive systems that only handle text — email bodies, JSON fields, data URIs, HTTP headers. It expands the data by roughly a third; it is a transport encoding, not compression.

It is also not encryption. Anyone can decode Base64 instantly, which is exactly what this page does. Use it to move data safely between text-only systems, never to hide it.

The URL-safe variant swaps + and / for - and _ so the result can sit in a query string or path without percent-encoding. Text is handled as UTF-8, so accented characters and emoji round-trip correctly.

Common uses

• Decoding a Base64 field from an API response.
• Embedding a small asset as a data URI.
• Inspecting the payload of a token or header.

Frequently asked questions

Is Base64 secure?

No. It is reversible by anyone with no key involved. If you need confidentiality, encrypt the data first and Base64 the ciphertext.

Why does decoding fail?

Usually the string is truncated, contains whitespace or line breaks from copying, or uses the URL-safe alphabet while standard decoding is selected. Toggle the URL-safe option and try again.

What is the trailing = for?

Padding. Base64 works in three-byte groups, and = marks that the final group was short. URL-safe encodings often drop it.