Zen Disk

Zen Disk is a clean, focused storage speed test for Android. Connect a drive, pick a location, press GO, and read clear write and read speeds in MB/s — with the context you need to trust each result.

WHY ZEN DISK
Find out whether a card, stick, or external drive is fast enough for the way you use it — before you rely on it for photos, video, backups, or everyday transfers.

WHAT IT TESTS
• Sequential write and read speed in MB/s
• The app's internal storage location, or a folder you choose on shared internal storage, an SD card, a microSD card, or a USB/OTG drive
• A live speed gauge, progress, and throughput charts as the test runs

HOW IT WORKS
• Zen Disk checks a location before it measures it, and a test starts only after you press GO.
• Each workload is sized automatically based on available space and observed speed.
• Tests use isolated temporary files that never overwrite your existing data.
• Fixed free-space headroom is kept so a run does not fill your storage.
• When a test ends, Zen Disk removes its temporary data; if storage was disconnected first, it retries cleanup when that same location returns.

UNDERSTAND EVERY RESULT
• Review up to 50 of your most recent completed tests in the on-device History.
• Each result carries the workload and timing details needed to interpret and reproduce it.

RESULTS & PRIVACY
Speeds reflect transfers through Android's Storage Access Framework, not raw block-device performance, and can vary with the device, drive, cable, adapter, filesystem, temperature, free space, and background activity.

Zen Disk has no accounts, no advertisements, no analytics, and no developer-operated data collection. Benchmark history and selected-location details stay on your device, subject to Android's backup settings.