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Sujal Khatri
Sujal Khatri

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Base64 Encode and Decode Without Breaking Emoji and Non-English Text

#webdev #tools #productivity #javascript

You have probably met Base64 in the wild: an API token, a data URI in an image tag, a long string pasted into a config file, or an email attachment. It looks like random letters, numbers, + and /, often ending in =.

Base64 is not magic. It is a way to represent any bytes as plain, safe text characters so they survive places that only handle text — URLs, JSON, emails, config files. Every 3 bytes become 4 characters, which is why encoded output is about 33% larger than the input.

The trap: emoji and non-English text break naive encoding

In the browser, the classic functions are btoa() and atob(). They only handle Latin-1 characters. Feed them an emoji or Hindi, Arabic, Chinese text and they throw an error or corrupt the result.

The fix is to encode the text as UTF-8 first, then Base64-encode those bytes. A Unicode-safe way in modern JavaScript:

// Encode, Unicode-safe
const bytes = new TextEncoder().encode("Hello 🌍");
const binary = String.fromCharCode(...bytes);
const encoded = btoa(binary); // SGVsbG8g8J+MjQ=

// Decode, Unicode-safe
const decodedBytes = Uint8Array.from(atob(encoded), c => c.charCodeAt(0));
const decoded = new TextDecoder().decode(decodedBytes); // Hello 🌍
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If you just need the answer once, you do not need to write this code or install anything.

Encode or decode in seconds, without installing anything

  1. Paste your text and click Encode, or paste a Base64 string and click Decode.
  2. Invalid Base64 shows a clear error instead of garbage output — that matters when you are debugging a token and cannot tell whether the string itself is broken.
  3. Copy the result with one click.

Try it here: https://bulktextkit.gt.tc/tools/base64-encoder-decoder.php?utm_source=devto

It runs entirely in your browser, so the text you paste never leaves your device — useful exactly when the string you are decoding is a real token.

One thing Base64 is not: encryption

Anyone can decode a Base64 string instantly. It hides nothing. Never use it to "protect" a password or secret — use real encryption for that. Base64 is for transport and compatibility, not security.

BulkTextKit Pro is a $19 one-time payment that adds bulk processing for up to 50 texts at once, saved presets, and CSV export — the 15 free tools stay free.

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