Free Online Base64 Encoder & Decoder

Encode plain text into Base64 format or decode Base64 strings. Built with UTF-8 byte stream support for emojis and international characters.

Plain Text (UTF-8)

Base64 Output / Input

About Free Online Base64 Encoder & Decoder

Encode and decode text, international characters, emojis, and binary files into standard RFC-4648 Base64 strings. ASToolHub features full UTF-8 Unicode encoding and in-browser binary file to Data URL conversion with zero server latency.

How to Use Free Online Base64 Encoder & Decoder Online

Choose Input Type

Select Text Mode to encode/decode strings or File Mode to convert images and documents into Base64 Data URLs.

Input Your Data

Type or paste your text into the editor, or drop any local file into the file upload box.

Encode or Decode

Click Encode to convert to Base64 ASCII or Decode to recover the original human-readable text.

Copy Result

Click Copy to clipboard to paste the Base64 string directly into your HTML, CSS, or API request.

Key Features & Privacy Benefits

Full Unicode & Emoji Support: Uses modern TextEncoder/TextDecoder APIs to handle non-Latin characters, Chinese/Japanese glyphs, and emojis without crashing.
Binary File to Data URL: Convert icons, PNGs, and fonts directly into 'data:image/png;base64,...' strings for inline CSS/HTML embedding.
Bidirectional Conversion: Seamlessly switch between encoding plain text into Base64 and decoding Base64 back into readable text.
Complete Offline Security: Encode authorization tokens and private keys with zero network transmission risk.

Frequently Asked Questions

What is Base64 encoding used for?

Base64 represents binary data in an ASCII string format, allowing images, cryptographic signatures, and binary objects to be transferred over text-only protocols like HTTP, JSON, and email.

Why do standard Base64 tools fail on emojis and special characters?

Legacy JavaScript functions (btoa/atob) only support Latin-1 characters. ASToolHub uses modern TextEncoder with UTF-8 byte arrays, supporting all global alphabets and emojis.

Does Base64 encryption provide security?

No. Base64 is an encoding scheme, not an encryption cipher. Anyone can decode a Base64 string. Do not use Base64 alone to protect secret data without encryption.