Free Base64 Encode & Decode Online

Encode or decode text as Base64, Base64URL, hex, URL encoding, HTML entities, Unicode escapes, ROT13 or binary with one simple API call.

Result

Press “Run” to see the result.

The Encode API converts text to and from the encodings developers deal with every day. Choose a scheme – base64, base64url, hex, url, html, unicode, rot13 or binary – and an action (encode, the default, or decode). Everything is UTF-8 aware, so Vietnamese, emoji and other non-ASCII text survive a round trip through Base64 or hex.

Details per scheme: base64url encodes without padding (JWT style); hex decoding ignores spaces and a 0x prefix; url uses percent-encoding (and turns + into spaces when decoding); html escapes & < > " ' and decodes named and numeric entities; unicode turns non-ASCII characters into \uXXXX escapes; binary outputs 8-bit groups separated by spaces.

Send text in the query string or a JSON body, or post the text as a raw text/plain body. The result comes back in a small JSON object together with the scheme and action used. Invalid input for a decode (for example broken Base64) returns a clear decode_error.

Use this in your code

curl -X POST "https://apibox.io.vn/v1/encode" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"text":"Xin chào APIBox","scheme":"base64"}'

const res = await fetch('https://apibox.io.vn/v1/encode', {
  method: 'POST',
  headers: {
    Authorization: 'Bearer YOUR_API_KEY',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    "text": "Xin chào APIBox",
    "scheme": "base64"
  }),
});
const data = await res.json();
console.log(data);

import requests

res = requests.post(
    "https://apibox.io.vn/v1/encode",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={"text": "Xin chào APIBox", "scheme": "base64"},
    timeout=30,
)
print(res.json())

<?php
$ch = curl_init('https://apibox.io.vn/v1/encode');
curl_setopt_array($ch, [
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_CUSTOMREQUEST => 'POST',
    CURLOPT_HTTPHEADER => ['Authorization: Bearer YOUR_API_KEY', 'Content-Type: application/json'],
    CURLOPT_POSTFIELDS => '{"text":"Xin chào APIBox","scheme":"base64"}',
]);
$response = curl_exec($ch);
print_r(json_decode($response, true));

API documentation → Get a free API key

FAQ

What is the difference between Base64 and Base64URL?

Base64URL replaces + and / with - and _ and drops the = padding so the result is safe in URLs and JWTs. Decoding with either scheme accepts both alphabets.

Does it handle Vietnamese and emoji?

Yes. Text is converted to UTF-8 bytes before encoding and decoded back from UTF-8, so "Xin chào" becomes "WGluIGNow6Bv" in Base64 and decodes back unchanged.

Is this encryption?

No. Base64, hex, URL encoding and ROT13 are reversible encodings that anyone can decode. To protect data use real encryption; to fingerprint it use /v1/hash.