Base64 Encode in JavaScript: btoa, Buffer, TextEncoder
Complete guide to Base64 encoding in JavaScript: btoa/atob, Node.js Buffer, TextEncoder for Unicode, and handling binary data.
Browser: btoa() and atob()
// Encode\nconst encoded = btoa('Hello World');\n// Decode\nconst decoded = atob(encoded);\n\n// Unicode-safe (btoa fails on non-Latin1)\nconst utf8Encode = btoa(unescape(encodeURIComponent('Hello 🌍')));\nconst utf8Decode = decodeURIComponent(escape(atob(utf8Encode)));Node.js: Buffer
// Encode\nBuffer.from('Hello').toString('base64')\n// Decode\nBuffer.from(b64, 'base64').toString('utf-8')\n// URL-safe\nBuffer.from('Hello').toString('base64url')Try It Free
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