Why is Base64 size larger than raw binary?

Because 4 ASCII characters (32 bits) are transmitted for every 3 original bytes (24 bits), resulting in an exact 33.3% size increase.

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DEVELOPER8 min2026-09

Web Encodings & Binary Data: Base64, Percent URL Encoding, UTF-8 & ASCII Explained

Demystify core internet encoding algorithms: Base64 bit-packing and padding, RFC 3986 URL percent-encoding, Unicode UTF-8, and binary stream payloads.

Encoding binary assets into plain-text protocols (HTTP, JSON, SMTP) requires robust standards such as Base64 and URL percent-encoding.

Learn 24-bit to 4-character mapping math, padding '=' rules, and RFC 3986 URI safety constraints.

1. Base64 Bit-Packing Math & Padding

Base64 converts chunks of 3 bytes (24 bits) into 4 six-bit printable symbols (A-Z, a-z, 0-9, +, /), introducing a 33% payload overhead.

Frequently Asked Questions

Answers to common questions.

Interactive Tools Related to this Guide

Try these free tools to apply the techniques covered in this guide.

Base64 Encoder

Encode text to Base64.

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Base64 Decoder

Decode a Base64 string.

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URL Encoder

Encode a URL or a parameter.

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URL Decoder

Decode an encoded URL.

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Text Diff

Compare two texts.

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