How to Use Base64 Encode & Decode — Complete Guide

FreeNo sign-upBrowser-basedNo upload

What is the Base64 Encode & Decode?

Convert text to and from Base64. Handles full Unicode (emoji, accents) correctly, and runs 100% client-side.

The tool is part of the Calabi free tools hub — a collection of 99+ browser-based utilities for developers, designers, and content creators. Everything runs client-side: your files and data never leave your device.

Open the Base64 Encode & Decode →

How to use the Base64 Encode & Decode

  1. Step 1: Type or paste your text (or a Base64 string).
  2. Step 2: Pick Encode or Decode.
  3. Step 3: Copy the result.

The tool updates in real time as you interact with it. No button-clicking required for most tools — results appear instantly.

Example

"Hello" → "SGVsbG8="

Privacy & security

The Base64 Encode & Decode is designed with privacy as a hard constraint, not an afterthought:

This architecture is particularly important for the Developer category of tools, where the inputs often contain sensitive or proprietary information.

Frequently asked questions

Is the Base64 Encode & Decode free?

Yes, completely free with no sign-up. Runs in your browser.

Is it safe to paste sensitive data?

Yes. The Base64 Encode & Decode runs entirely client-side in your browser. Nothing is sent to a server. You can verify this with your browser's network inspector — you'll see zero outbound requests when you use the tool.

Does it work offline?

Once the page is loaded, yes. The tool logic is a self-contained JavaScript bundle with no runtime API calls.

What browsers are supported?

Any modern browser — Chrome, Firefox, Safari, Edge. Internet Explorer is not supported.

About Developer utilities

The Base64 Encode & Decode is part of the Developer utilities category in the Calabi tools hub. Encode text to Base64 or decode Base64 back to text, UTF-8 safe, entirely in your browser. Nothing is uploaded. All tools in this category run entirely in your browser with no server involvement.

Browse all 99 free tools →

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