Eight checks. One verdict. Is your machine worthy of the bench?
Eight checks from the bench. Reaction, display, graphics, network, and more. Ninety seconds, one rank, entirely on your device.
What is the device certification?
The certification battery is the whole workshop in one sitting: a curated pass over the checks that matter most for how a machine actually feels in use. Passive stages read what your browser already knows, active stages ask for a few seconds of your hands, and the result is stamped into a washi certificate with one of five Shokunin ranks, from 見習い (apprentice) to 名人 (grandmaster). Nothing is uploaded; the certificate image and its share link are generated entirely on your device.
Questions from the bench
What does the battery actually measure?
Eight stages: display refresh and resolution, a short GPU stress render, memory headroom, network round-trip time and jitter, plus a few active checks such as reaction time and keyboard rollover on desktop, or multitouch and gyroscope steadiness on phones. Each stage reuses the same measurement core as the standalone tool on this site.
Does any of my data leave the device?
No. Every check runs in your browser, and the share link encodes only the mode, the eight stage scores, the date, and a generic device line such as the OS, browser, and resolution. There is no backend, no account, and nothing is stored.
Why did a stage say 対応外 (not measurable)?
Some browsers keep certain readings to themselves, such as audio output latency or the memory API. When that happens the stage is marked not measurable and scores a neutral half of its points, so an unsupported browser is never mistaken for a bad device.
How are the ranks calibrated?
Generously at the bottom, stingily at the top. A typical mid-range laptop lands around Craftsman (60 to 74). Takumi and Meijin are deliberately hard to reach, so a gold seal means the machine genuinely earned it.
Can I retake the test?
As often as you like. The battery is designed to finish in about ninety seconds, and skipping any active stage still issues a certificate with that line marked 未検 (untested).