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Disk Speed Test is a lightweight storage benchmark for Windows, built as a modern alternative to CrystalDiskMark. It measures sequential and random read/write speed, IOPS and latency for SSDs, NVMe drives, hard disks, USB sticks, SD cards and network drives.
Unlike CrystalDiskMark, which runs Microsoft's DiskSpd tool for each test, Disk Speed Test has its own native I/O engine written in Rust. Everything ships as a single small executable with no installer and no external tools. It uses unbuffered, overlapped I/O, so results reflect the drive itself rather than the Windows file cache.
It offers the familiar tests (SEQ1M Q8T1, SEQ1M Q1T1, RND4K Q32T1, RND4K Q1T1) and profiles, plus things CrystalDiskMark doesn't show: a live throughput graph, latency percentiles (p50 to p99.99), per-run results and an optional mixed read/write test. Results can be copied or saved as text in the familiar CrystalDiskMark layout.
Features
- Single portable executable: no installer, no DiskSpd, no external tools
- Native I/O engine written in Rust, using unbuffered overlapped I/O that bypasses the Windows file cache
- Sequential and random read/write tests with adjustable block size (4 KiB to 8 MiB), queue depth (1 to 512) and threads (1 to 64)
- Familiar default tests: SEQ1M Q8T1, SEQ1M Q1T1, RND4K Q32T1, RND4K Q1T1
- Profiles: Default, Peak Performance, Real World Performance and Demo
- Presets for regular drives, NVMe SSDs and flash memory (USB / SD)
- Optional mixed read/write test with adjustable ratio (R90/W10 to R10/W90)
- Results in MB/s, GB/s, IOPS or microseconds (μs)
- Live throughput graph while tests run
- Detailed latency stats: average, min, max and p50/p90/p99/p99.9/p99.99
- Best-of-N runs (1 to 9) after a warm-up run that isn't counted
- Adjustable test file size (16 MiB to 64 GiB), measure time and pause between tests
- Random or all-zero test data
- Shows each drive's model, connection type (NVMe, SATA, USB…), SSD/HDD, file system and free space
- Test any drive or any folder, including network drives
- Copy or save results as text, with a comment field
- Dark and light themes, plus zoom from 80% to 200%
- Settings saved automatically to a small ini file next to the exe
- Test file is always cleaned up, even if you stop a test or close the app
Project Samples
