Record with the microphone or upload an audio file to get started
Options
Tips and other info
Record in a quiet environment.
Blue regions of the graph indicate stretches of time with low pitch clarity, such as silence or too much extraneous noise.
The pitch detection doesn't work well with polyphony (e.g. double stops on a string instrument), so sections with lots of simultaneous notes will appear as low clarity
The calculation of accuracy assumes that the measured pitch is within 50 cents (or a quartertone) of the intended pitch. If the measured pitch was more than that amount off, the accuracy reading is unreliable.
You can zoom and pan the graph.
All data and processing is handled completely locally on your browser.
I wrote more about this project at this post, for those interested in the details of its implementation.