Base64 Encoder & Decoder Online

Convert text and binary data to and from Base64 format in real time. 100% client-side processing keeps your sensitive tokens and credentials completely private.

At a glance

Base64 Encoder & Decoder is a free, client-side tool that encodes text and files to Base64 or decodes Base64 strings to readable text instantly. It copies formatted results directly into your code or terminal. See decoded and encoded outputs update synchronously as you type. Nothing is uploaded and no sign-up is needed — everything runs on your device.

Live Convert URL-Safe (-_)

Plain Text Input 0 chars • 0 B

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Base64 Output 0 chars • 0 B

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Why Use This Base64 Encoder & Decoder?

Complete UTF-8 & Emoji Support: Safely encodes international characters, mathematical symbols, and emojis without encoding errors.

100% Client-Side Privacy: Passwords, API tokens, and JWT payloads are parsed strictly in your browser memory.

Live Real-Time Conversion: See decoded and encoded outputs update synchronously as you type.

One-Click Clipboard Copy: Copy formatted results directly into your code or terminal.

How to Use Base64 Encoder & Decoder

Choose Mode

Select either 'Encode' (Text to Base64) or 'Decode' (Base64 to Text) from the top tab switcher.

Enter Text

Paste or type your string into the input editor or load a sample string.

Copy or Download

Click 'Copy Output' to grab your encoded/decoded text or download it as a local text file.

Worked example: Hello World Text to SGVsbG8 Encoding

The engine converts the string to UTF-8 bytes with TextEncoder, builds a binary string and calls btoa for encoding (atob plus TextDecoder for decoding), all in browser memory.

Plain Text Input Source

Hello, World!

Base64 Encoded Output Processed

SGVsbG8sIFdvcmxkIQ==

Technical Specifications & Engine Details

Technical specifications and engine details for Base64 Encoder & Decoder
Specification	Details
Supported Formats	TXT, BIN, DATA → TXT, BASE64
Execution Mode	100% Client-Side In-Browser (client)
Browser Requirements	Requires modern web browser with ECMAScript 6+ and standard DOM Web APIs.
Performance Constraints	Client browser memory limit (typically 1–2 GB RAM); processing speed depends on local device CPU.

Maintained by Pragyan Pahadi

100% Client-Side Privacy Guarantee

Your data remains strictly in your local browser memory. Zero information is transmitted to external servers.

Frequently Asked Questions

What is Base64 encoding used for?

Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format. It is widely used in data URIs, email attachments (MIME), HTTP Basic Authentication, and JSON API payloads.

Can this tool handle UTF-8 characters and emojis?

Yes. Traditional JavaScript btoa fails on non-ASCII characters. Our engine uses standard UTF-8 byte encoders so international text, accents, and emojis work flawlessly.

Is my sensitive data secure?

Absolutely. All encoding and decoding operations occur 100% locally in your browser. No strings are ever transmitted over the network.

Methodology

This tool runs entirely in your browser. The example above shows a representative input and the result it produces.

Last updated October 2026.