# [[Disk speed testing using f3]]
_Created: 2025-08-27_ | #performance | [[010 System Administration MOC|System Administration]]
- Repository: https://github.com/AltraMayor/f3
- Docs: https://fight-flash-fraud.readthedocs.io
>[!note] Card used for tests below
>The tests below were conducted on **SanDisk Extreme UHS-I U3 V30 A1 32GB microSDHC Card**. It is rated for 100MB/s read speed and 60MB/s write speed.
>[Tests](https://www.cameramemoryspeed.com/reviews/sd-cards/sandisk-extreme-100mbs-u3-v30-a1-32gb-microsdhc-memory-card/) have shown this to give writes around 70 MB/s and reads about 99.5 MB/s.
>The data below shows similar write speed but slower read speed.
## Testing writes
```shell-session
$ f3write /Volumes/sandisk32g/
F3 write 9.0
Copyright (C) 2010 Digirati Internet LTDA.
This is free software; see the source for copying conditions.
Free space: 29.51 GB
Creating file 1.h2w ... OK!
...
Creating file 30.h2w ... OK!
Free space: 54.38 MB
Average writing speed: 70.05 MB/s
```
## Testing reads
```shell-session
$ f3read /Volumes/sandisk32g/
F3 read 9.0
Copyright (C) 2010 Digirati Internet LTDA.
This is free software; see the source for copying conditions.
SECTORS ok/corrupted/changed/overwritten
Validating file 1.h2w ... 2097152/ 0/ 0/ 0
...
Validating file 30.h2w ... 950353/ 0/ 0/ 0
Data OK: 29.45 GB (61767761 sectors)
Data LOST: 0.00 Byte (0 sectors)
Corrupted: 0.00 Byte (0 sectors)
Slightly changed: 0.00 Byte (0 sectors)
Overwritten: 0.00 Byte (0 sectors)
Average reading speed: 90.92 MB/s
```