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Base64 Conversion Suite

Free, lightning-fast in-browser converters for Images, PDFs, Audio, Video, Text, Hex, and HTTP Basic Auth.

Base64 Decoders

Base64 to Image Converter

Decode Base64 strings and Data URIs back to downloadable PNG, JPG, WebP, SVG, and GIF images.

Base64 Decoders

Base64 to PDF Converter

Convert Base64 strings into viewable, downloadable PDF documents in an embedded viewer.

Base64 Decoders

Base64 to Text / ASCII Converter

Decode Base64 strings to readable plain text and ASCII with full UTF-8 and emoji support.

Base64 Decoders

Base64 to Audio Converter

Convert Base64 audio strings into playable sound in an HTML5 player and download MP3, WAV, and OGG.

Base64 Decoders

Base64 to Video Converter

Convert Base64 video strings into playable video in an HTML5 player and download MP4/WebM files.

Base64 Decoders

Basic Auth Header Decoder

Decode HTTP Authorization: Basic headers to extract usernames, passwords, and API credentials.

Base64 Decoders

Base64 to Hex Converter

Decode Base64 strings into formatted Hexadecimal byte arrays with custom spacing and case.

Base64 Decoders

Base64 to File Converter

Reconstruct and download any binary file (ZIP, DOCX, XLSX, PDF, binary) from Base64 strings.

Base64 Encoders

Image to Base64 Encoder

Encode PNG, JPG, SVG, WebP, and GIF images to Base64 Data URIs, HTML img tags, and CSS rules.

Base64 Encoders

PDF to Base64 Encoder

Convert PDF documents into clean Base64 encoded strings and Data URIs for REST APIs and storage.

Base64 Encoders

Text to Base64 Encoder

Encode plain text, UTF-8 strings, and emojis into standard and URL-Safe Base64 strings.

Base64 Encoders

Audio to Base64 Encoder

Convert MP3, WAV, and OGG sound files into Base64 Data URIs for web inlining and APIs.

Base64 Encoders

Video to Base64 Encoder

Convert MP4 and WebM video clips into Base64 Data URIs to inline video animations into HTML.

Base64 Encoders

Hex to Base64 Converter

Convert raw Hexadecimal byte sequences into compact Base64 strings for REST APIs.

Base64 Encoders

File to Base64 Encoder

Convert any binary file (ZIP, DOCX, XLSX, PDF) into Base64 strings and Data URIs.

Comprehensive Guide to Base64 Binary-to-Text Encoding

Base64 is an essential standard in modern web development. By translating raw 8-bit binary octets into a safe 6-bit ASCII subset, developers can transport binary assets through communication channels that only support text—such as JSON REST APIs, inline HTML documents, CSS stylesheets, and XML documents.

Popular Base64 Conversions

  • Images: Embed lightweight logos and icons directly into HTML <img src="data:image/png;base64,..."> to eliminate HTTP roundtrips.
  • PDFs: Preview, sign, and download PDF documents in JavaScript without requiring server-side rendering.
  • Authentication: Decode and verify HTTP Basic Auth headers (Authorization: Basic ...).
  • Audio & Video: Embed sound effects and short video clips directly into web applications.

Frequently Asked Questions

What is Base64 encoding and why is it used?

Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format using 64 printable characters (A-Z, a-z, 0-9, +, /). It allows binary media (images, PDFs, audio, fonts) to be safely embedded inside text-based formats like HTML, CSS, JSON, and email protocols (MIME) without character corruption.

Are all Base64 converters on this site 100% client-side and private?

Yes! Every single converter (Image to Base64, Base64 to PDF, Audio, Video, Basic Auth, and Hex) executes locally in your web browser memory using standard Web APIs. No images, PDF documents, or private credentials are ever transmitted to an external server.

How much does Base64 encoding increase file size?

Base64 increases the raw binary file size by approximately 33% (every 3 binary bytes become 4 ASCII characters, plus optional padding '=').

What is a Data URI and how do I use it in HTML and CSS?

A Data URI allows you to embed files inline using the syntax 'data:[mediatype];base64,[data]'. For example: '<img src="data:image/png;base64,..." />' in HTML or 'background-image: url("data:image/png;base64,...");' in CSS.

What is the difference between standard Base64 and URL-Safe Base64?

Standard Base64 uses '+' and '/' characters, which have special meanings in URL query strings. URL-Safe Base64 substitutes '-' for '+' and '_' for '/', and omits trailing '=' padding to prevent URL parsing errors.

Can I decode Basic Authentication headers with Base64?

Yes! HTTP Basic Auth encodes credentials as 'Authorization: Basic base64(username:password)'. Our Basic Auth tool instantly extracts the username and password in browser memory.