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Base64 Converter

Convert text to Base64 and back in your browser. Full UTF-8 support for Chinese, Japanese and emoji, with clear errors for bad padding.

All processing happens locally in your browser. Files are never uploaded.

Input

Introduction

Base64 Converter lets you encode plain text into Base64 and decode Base64 back to text. Unlike the built-in btoa function, this tool treats input as UTF-8, so Chinese, Japanese and emoji survive round-trips. Invalid characters and broken padding are reported instead of producing garbage.

Features

  • UTF-8 safe encoding and decoding
  • Correctly handles CJK and emoji
  • Detects invalid Base64 characters
  • Reports bad padding and length
  • Swap, copy and download in one click

How to use

  1. 1Type or paste your text or Base64 string.
  2. 2Click Text → Base64 to encode, or Base64 → Text to decode.
  3. 3Read any error about invalid characters or padding.
  4. 4Copy or download the result.

Frequently asked questions

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