Base64 Encoder & Decoder

Free Base64 encoder and decoder — byte-accurate, so it round-trips any file or binary losslessly (unlike tools that crash on non-text). UTF-8 text, URL-safe variant for JWTs, MIME line-wrapping, data-URI builder, file upload, and a hex view for binary.

Base64 Encoder/Decoder — Convert Text and Files to Base64

Base64 is a text encoding that lets you embed binary data (images, files) into text-only contexts — emails, JSON APIs, HTML data URIs, JWT tokens, and configuration files. Our Base64 Encoder converts plain text or files into Base64, and decodes Base64 strings back to their original form. Useful for developers, integrators, and anyone working with web APIs.

Unlike most online converters — which are built on the browser's btoa/atob and throw an error the moment you decode the Base64 of a real file (a PNG, PDF or ZIP is rarely valid UTF-8) — this tool works at the byte level. Any byte sequence round-trips exactly: encode a file, decode it back, and you get the identical bytes. When decoded data isn't text, you get a hex view and a one-click download instead of a crash.

Paste text, paste a Base64 string, or upload a file. Get instant encoding or decoding. No signup, no cost.

How to Use Base64 Tools

1. Choose Mode

Encode (text/file → Base64) or Decode (Base64 → text/file).

2. Paste or Upload

Paste your text or Base64 string, or upload a file (image, PDF, any binary).

3. Auto-Convert

Conversion happens instantly. Output appears below ready to copy or download.

4. Copy or Download

Copy the output to clipboard or download as a file. Perfect for pasting into code or curl commands.

All conversions happen in your browser. Your data is never sent to any server.

Base64 Tool Features

Lossless for Any File

Byte-accurate encoding and decoding. Any binary — PDF, image, ZIP, random bytes — round-trips exactly, with no corruption and no "URI malformed" error.

URL-Safe Variant

Toggle URL-safe Base64 (uses - and _ instead of + and /, no padding) for JWTs and URL parameters. The decoder accepts both alphabets automatically.

Data URI Builder

For images, generate a complete data: URI ready to paste into HTML or CSS — with a live image preview when you decode one back.

Full Unicode (UTF-8)

Correctly handles emojis, Hindi, Chinese, Arabic and every other script — no broken characters, no deprecated escape() tricks.

Tolerant Decoding

Paste Base64 with line breaks, spaces, missing padding or a full data: URI prefix — it still decodes. Invalid input gets a clear message naming the bad character and position.

MIME Line-Wrapping

Optionally wrap output at 64 or 76 characters per line for email (MIME), PEM keys and certificates.

Live Conversion

Encoding and decoding happen as you type, with running size and overhead stats — no "convert" button to click.

Free and Private

All processing happens in your browser. Files and text never leave your device — no signup, no tracking.

Base64 Encoder/Decoder — FAQs

No. Base64 is encoding, not encryption. Anyone with the encoded string can decode it back to the original. Don't use Base64 to "hide" sensitive information — use real encryption (AES, RSA) for that.

Base64 represents 3 binary bytes as 4 ASCII characters, so output is approximately 33% larger than input. The trade-off is gaining the ability to safely embed binary data into text-only systems.

When the encoded string goes into a URL or JWT. Standard Base64 uses + and / which are reserved characters in URLs. URL-safe Base64 uses - and _ instead, avoiding the need for percent-encoding.

Many browser-based converters run the decoded bytes through a UTF-8 text step (decodeURIComponent(escape(atob(...)))). A PNG, PDF or ZIP isn't valid UTF-8, so that step throws "URI malformed" and you get nothing back. This tool decodes to raw bytes first, so any file round-trips exactly. If the result isn't text, you'll see it in hex and can download it as a file.

Yes. The decoder strips whitespace and line breaks (as in MIME email, PEM keys and certificates), tolerates missing = padding (common in JWTs), accepts both the standard and URL-safe alphabets, and even lets you paste a full data:...;base64, URI. If a character genuinely isn't valid Base64, you get a clear error naming it and its position.

Yes, completely free. No signup, and everything runs locally in your browser.

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