v149 · JavaScript
Binary File Tools
Drop any small file onto the page. The demo reads it as a Uint8Array, encodes to base64 via toBase64() and hex via toHex(), and shows both outputs — all client-side, nothing uploaded.
Feature detection: checking…
Drop a file here
or click to choose (images, text, JSON, SVG — keep it small!)
Name: —
Size: —
Type: —
Base64 length: —
Hex length: —
// Read file as ArrayBuffer, wrap in Uint8Array
const file = event.target.files[0];
const buf = await file.arrayBuffer();
const arr = new Uint8Array(buf);
// ① Base64 (NEW in Chrome 149)
const b64 = arr.toBase64();
// ② URL-safe base64 (NEW in Chrome 149)
const b64url = arr.toBase64({ alphabet: "base64url" });
// ③ Hex string (NEW in Chrome 149)
const hex = arr.toHex();
// Build data URL for images
const dataUrl = `data:${file.type};base64,${b64}`;
img.src = dataUrl;see also
- Encode & Decode — text round-trip
- Hex Inspector — byte-by-byte view
- URL-Safe Base64 — alphabet comparison
implementation reference
Need the exact API surface, compatibility boundaries, errors, lifecycle, and source links? Read the matching gendn reference ↗