How to Find a Song’s Key and BPM
Updated June 2026 · by Loopin
Knowing a beat’s key and tempo makes everything easier — writing melodies that fit, singing in tune, and matching ideas together. Here’s how to find both.
Why key and BPM matter
BPM (beats per minute) is the tempo — it sets the pace of your flow and how your syllables land. The key is the home note set your melody and harmonies revolve around; singing or toplining in the wrong key is what makes a take feel “off.”
Finding the BPM
You can tap along to the beat for four bars and average it, or use a tempo detector. The fastest way: let it detect automatically. Loopin reads the BPM the moment you import a beat.
Finding the key
By ear, hum the note the song “resolves” to and find it on a keyboard. Or use automatic detection — Loopin estimates the key for your imported beat so you can write in tune without guessing.
Use it while you write
With key and BPM known up front, your melodies fit, your harmonies stack, and your features match. It’s a small thing that makes finished songs sound a lot more professional — and it pairs well with a clean master at the end.