What is Base64 used for?

Base64 represents binary data using only 64 printable ASCII characters, so it can travel safely through text-only systems. It’s common in data URIs, email attachments (MIME), JSON Web Tokens, HTTP basic auth headers, and anywhere binary needs to be embedded in text.

Does it handle emoji and accented characters?

Yes. The encoder converts your text to UTF-8 bytes before encoding, so emoji, accented letters and characters from any language round-trip perfectly — something the browser’s raw btoa() can’t do on its own.

What does “URL-safe” mean?

Standard Base64 uses “+” and “/”, which have special meaning in URLs. URL-safe Base64 (base64url) replaces them with “-” and “_” and usually drops the “=” padding, so the value can be dropped into a URL or filename without escaping.

Why won’t my Base64 decode?

The most common causes are characters that aren’t part of the Base64 alphabet or a truncated string. This tool ignores spaces and line breaks and restores missing padding, so if it still reports an error, the input is likely incomplete or not actually Base64.

Is my data sent to a server?

No. All encoding and decoding happens locally in your browser. Whatever you paste never leaves your device, and the tool keeps working offline once the page has loaded.

Is Base64 a form of encryption?

No — it’s encoding, not encryption. Base64 is fully reversible by anyone and provides no security or secrecy. Never use it to protect sensitive information; use real encryption for that.

Base64 Encoder / Decoder

Encode text to Base64 or decode Base64 back to text — UTF-8 safe, with URL-safe output.

Developer

Your files never leave your device.

How to use Base64 Encoder / Decoder

Choose encode or decode

Use the toggle at the top to pick a direction — Encode turns text into Base64, Decode turns Base64 back into text.
Type or paste your input

Drop text (to encode) or a Base64 string (to decode) into the box. The result appears instantly below — there’s no button to press.
Tweak the options

When encoding, turn on “URL-safe output” if the result needs to go in a URL or filename. When decoding, spacing and line breaks are ignored automatically.
Copy, download or chain it

Copy or download the output in a click, or hit “Use result as input” to flip the mode and feed the result straight back in for a quick round-trip check.

Key features

Live, two-way conversion — encode and decode with a single toggle
Full UTF-8 support: emoji, accents and non-Latin scripts round-trip cleanly
URL-safe (base64url) output option with padding stripped
Forgiving decoder that ignores whitespace and repairs missing padding
Clear, friendly errors when the input isn’t valid Base64
One-click copy and download; 100% in-browser, nothing uploaded

About Base64 Encoder / Decoder

A fast, no-nonsense Base64 encoder and decoder that works entirely in your browser. Switch between Encode and Decode, and the result updates live as you type. Encoding is fully Unicode-aware — emoji, accents and non-Latin scripts all round-trip correctly because the text is converted through UTF-8 first. Need Base64 for a URL or filename? Flip on URL-safe output to swap “+/” for “-_” and drop the padding. Decoding is forgiving too: it accepts standard and URL-safe input, ignores stray spaces and line breaks, and fixes missing padding, with a clear message if the input really isn’t valid Base64. Copy or download the result in one click. Nothing is ever uploaded — it’s all local, free, and free of sign-ups and limits.

Last updated 2 June 2026.

Frequently asked questions

What is Base64 used for?: Base64 represents binary data using only 64 printable ASCII characters, so it can travel safely through text-only systems. It’s common in data URIs, email attachments (MIME), JSON Web Tokens, HTTP basic auth headers, and anywhere binary needs to be embedded in text.
Does it handle emoji and accented characters?: Yes. The encoder converts your text to UTF-8 bytes before encoding, so emoji, accented letters and characters from any language round-trip perfectly — something the browser’s raw btoa() can’t do on its own.
What does “URL-safe” mean?: Standard Base64 uses “+” and “/”, which have special meaning in URLs. URL-safe Base64 (base64url) replaces them with “-” and “_” and usually drops the “=” padding, so the value can be dropped into a URL or filename without escaping.
Why won’t my Base64 decode?: The most common causes are characters that aren’t part of the Base64 alphabet or a truncated string. This tool ignores spaces and line breaks and restores missing padding, so if it still reports an error, the input is likely incomplete or not actually Base64.
Is my data sent to a server?: No. All encoding and decoding happens locally in your browser. Whatever you paste never leaves your device, and the tool keeps working offline once the page has loaded.
Is Base64 a form of encryption?: No — it’s encoding, not encryption. Base64 is fully reversible by anyone and provides no security or secrecy. Never use it to protect sensitive information; use real encryption for that.