Test files,
precise to every byte
Images · video · audio · documents — generated byte by byte in your browser. Built for upload limits, MIME validation, magic-byte checks, codec pipelines and boundary tests. No server, no upload, no waiting.
SPECIMEN rotates every 5 seconds · hover to pause
Custom file generator
Set dimensions, duration or row count — or pad the file to an exact target byte size for boundary rules such as “must not exceed 5 MB”.
* Padding appends 0x00 NULL bytes after a valid file structure. Browsers and decoders can still parse images and audio while the physical size remains byte-exact — ideal for upload-limit testing.
The toast reports the exact byte count
Preset resource library 24 files
Click a card to preview · hover for live thumbnails · generated on demand
File inspector
Drop in any file — locally read its magic-byte signature, compute SHA-256, and detect disguised extensions or padding. Data never leaves your device.
WAV / WebM / ZIP / MP3 / SVG / JSON…
Automation script templates
Connect preset files to CI — copy and run.
POPULAR SEARCH PATHS
Find the right test file by task
Start with a ready-to-download sample or follow a verified QA workflow. Every published file includes exact bytes, a stable URL, and SHA-256 metadata.