What is Base64 encoding used for?

Base64 converts binary data into a text-safe format. It is commonly used in email attachments, data URIs, JWTs, and API payloads to transmit binary data as plain text.

Is my data sent to a server?

No. Encoding and decoding happen entirely in your browser.

Does Base64 encrypt my data?

No. Base64 is an encoding scheme, not encryption. Anyone who receives the Base64 string can decode it instantly. Do not use it to hide sensitive information.

Can I encode files, not just text?

Yes. Drop a file into the file tab to get its Base64 representation, useful for embedding images in CSS or HTML.

Base64 Encoder / Decoder

Base64 encoder and decoder is a browser-based utility for converting text and binary data to and from the Base64 format. Encode strings, decode API payloads, or convert files to data URIs entirely in your browser.

Plain text

Base64

BASE64

Base64 Encode

Converts UTF-8 text to Base64 encoding. Handles Unicode characters correctly.

Runs entirely in your browser

All Base64 tools

File encoding, decoding, and image data URIs.

Base64 Encode Text

Encode any text to Base64 instantly in your browser. All processing runs in your browser.

Base64 Decode

Decode Base64 strings back to plain text in your browser. Instant, private.

File to Base64

Convert any file to a Base64 string in your browser. All processing runs in your browser, works offline.

Image to Data URI

Convert an image to a Base64 data URI for inline embedding in HTML or CSS. Runs entirely in your browser.

How to encode or decode Base64

Choose "Encode" or "Decode" mode depending on what you need.
Paste your text or data into the input area.
The result appears instantly in the output area below.
Click "Copy" to copy the encoded or decoded result to your clipboard.

Common uses

Encoding binary data (images, files) as Base64 for embedding in JSON or HTML
Decoding Base64-encoded strings from APIs, JWTs, or data URIs, use JWT decoder to inspect full token claims
Checking what data is stored inside a Base64-encoded field, pair with URL encoding when transmitting in query strings

Technical specification

Algorithm or formula: Standard Base64 encoding per RFC 4648. Text mode wraps the browser primitives in a UTF-8 safe layer so non-ASCII characters round-trip correctly.
Browser API or library: Native btoa and atob combined with TextEncoder and TextDecoder for UTF-8. File mode uses FileReader.readAsDataURL.
Input limits: Files capped at 10 MB to keep encoding instantaneous. Text input is bounded by available browser memory.
Output: Plain Base64 string, or a full data URI (data:{mime};base64,...) for files.
Known limitations: Base64-url (with - and _) is decoded automatically but not produced. Output is not chunked into 76-character lines (MIME variant).

Frequently asked questions

What is Base64 encoding used for?: Base64 converts binary data into a text-safe format. It is commonly used in email attachments, data URIs, JWTs, and API payloads to transmit binary data as plain text.
Is my data sent to a server?: No. Encoding and decoding happen entirely in your browser.
Does Base64 encrypt my data?: No. Base64 is an encoding scheme, not encryption. Anyone who receives the Base64 string can decode it instantly. Do not use it to hide sensitive information.
Can I encode files, not just text?: Yes. Drop a file into the file tab to get its Base64 representation, useful for embedding images in CSS or HTML.

Reviewed and tested May 26, 2026.