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Base64 Encoder / Decoder

Encode text or files to Base64, or decode Base64 strings back to plain text.

Free Base64 Encoder & Decoder — Convert Text & Files to Base64

Our free online Base64 encoder and decoder converts text strings and files to and from Base64 format instantly. Whether you're encoding images for data URIs in CSS, decoding JWT tokens for debugging, generating Basic Authentication headers for API testing, or working with email attachment encoding, our professional Base64 codec tool handles every common use case with no signup or software installation.

Base64 encoding is essential infrastructure for modern web development, email systems, and data transmission protocols. It safely represents binary data — images, files, encrypted content — as ASCII text that can be embedded in JSON payloads, URL parameters, HTML attributes, and email headers. Our Base64 encoder/decoder supports both text and file conversion in either direction, with output in standard Base64 or URL-safe Base64 formats depending on your application requirements.

Key Features

Bidirectional Conversion

Encode plain text to Base64 or decode Base64 strings back to original text instantly.

File Encoding Support

Encode images, PDFs, and binary files to Base64 data URIs for embedding in CSS, HTML, and JSON.

URL-Safe Variant

Optionally output URL-safe Base64 (using - and _ instead of + and /) for inclusion in URLs and JWT tokens.

Real-Time Conversion

Output updates instantly as you type — no need to click an encode/decode button after every change.

How to Use This Tool

  1. 1

    Choose your direction: encode (text → Base64) or decode (Base64 → text).

  2. 2

    Paste your text or Base64 string into the input area, or upload a file to encode.

  3. 3

    View the converted output in the result area instantly.

  4. 4

    Copy the output to your clipboard or download as a file.

Common Use Cases

Data URI Generation

Encode small images and SVG icons as Base64 data URIs for direct embedding in CSS background-image and HTML img src.

JWT & API Token Debugging

Decode the header and payload sections of JSON Web Tokens to inspect claims, expiration, and signing algorithm.

Basic Authentication Headers

Generate Base64-encoded credentials for HTTP Basic Auth headers in API testing with Postman, curl, or custom clients.

Email Attachment Encoding

Encode files for inclusion in MIME multipart email messages, raw SMTP transactions, and email API payloads.

Why Choose Our Base64 Encoder/Decoder?

Our Base64 encoder and decoder is a free professional developer tool used by web developers, API engineers, security researchers, and DevOps teams every day. Unlike command-line tools requiring technical setup or paid developer utilities with feature paywalls, our browser-based Base64 codec delivers instant text and file conversion in both directions with no signup, no software installation, and complete privacy through client-side execution. Base64 encoding underpins modern web infrastructure — from data URI image embedding to JWT authentication tokens to email attachment encoding — making this tool essential for any developer working with web APIs, email systems, or binary data transmission. With support for standard and URL-safe Base64 variants plus file upload encoding, our codec handles every common Base64 use case in one fast online tool.

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