Workbench
…or drop one here. Files are read in this page and never uploaded.
Output
Use the arrow keys to inspect each character.
Benchmark
Measures how fast this browser encodes and decodes random data, next to its own base64 and hex. It runs in a background worker, so the page stays responsive. Results depend on the device and are not sent anywhere.
Alphabet
16384 characters, U+4E00 to U+8DFF, one for each 14-bit value, shown 256 at a time. Six end markers, U+3D01 to U+3D06, record the length of a short last group.