How to Start Practicing with Piano Trainer

Piano Trainer is a browser-based piano practice tool that loads a MIDI file, listens to your acoustic or digital piano through your microphone, and scores how accurately you play the notes. To start, open the site, load a .mid file, pick a mode and hand, then grant microphone access and calibrate by holding A4 on your piano for about one second. Everything below follows the controls shown on the page itself.

Before You Begin

You need three things:

• A .mid file (MIDI, not audio). The page states plainly: "Load a MIDI file to start practicing piano with real-time mic feedback."
• A piano you can play — acoustic or digital — positioned so your microphone can hear it.
• A browser session where you can allow microphone access. The mic is required for the scored modes because detection works "via microphone."

If you don't have a file ready, the page offers a Demo button, so you can explore the interface before committing your own music.

Step-by-Step: Your First Session

1. Load your MIDI file

Click Load MIDI, or drag and drop a .mid file anywhere on the page. The header will change from "No file loaded" to showing your loaded track.

2. Choose a mode

The page gives you two modes:

Start with Watch Mode if you're learning the notes, then switch to Play Along when you want feedback.

3. Choose which hand to practice

Under Hand, select Both Hands, Right Hand, or Left Hand. The page describes this as "Practice left or right hand independently," which is useful for isolating a difficult part before playing hands together.

4. Allow microphone access

Press M or click the mic control to enable detection. Your browser will ask for permission — accept it. Without this, Play Along can't score you.

5. Calibrate tuning

Click Calibrate Tuning, then "Play A4 on your piano (hold for 1 second)." The panel shows A4 and Waiting... while it listens. When it captures the note, the calibration closes and you're ready. This step matters because detection compares the pitch it hears against the expected notes — if your piano is sharp or flat relative to the reference, you'll get false "wrong" results.

6. Play

Press Space to start playback. Notes fall toward the keyboard and the sheet music scrolls. Play along; the session tracks correct, missed, and wrong notes in real time.

7. Review your results

When the song ends, a Session Complete panel appears with your Accuracy percentage and the correct / missed / wrong counts. From there you can Retry or Close.

Keyboard Shortcuts

Tuning the Detection to Your Setup

The controls panel exposes several settings that affect how forgiving or strict detection is:

• Speed — playback rate (shown as 1.00x by default). Slow it down when learning a passage.

• Noise Cancel — options include None, Spectral, and DeepFilterNet3. If your room is noisy or your mic picks up hum, try a cancellation option.

• Detection — the note-detection model. The page lists these with their reported F1 scores:

  • Standard (instant) — fastest, no accuracy figure given.
  • Basic Pitch (~80% F1)
  • Transkun V1 (~94% F1)
  • Transkun V2 SOTA (~98% F1)
  • ⚡ Kong/Bytedance (~90% F1)

  Higher F1 generally means fewer misdetections, but the heavier models may add latency. If you're getting spurious "wrong" notes, try a higher-accuracy model; if you need instant response, stay on Standard.

• Tune Clarity (0.63), Speed (3fr), Release (8fr) — fine-tuning parameters for the detection pipeline. Adjust these only if the defaults aren't working for your piano's tone.

• Volume (80%) — playback volume of the reference track.

Common Snags

• Nothing scores. The mic isn't active. Press M and confirm browser permission. Detection only works in Play Along mode.
• Everything registers as wrong. Run Calibrate Tuning again and hold A4 steadily for the full second. Also check that the reference track's volume isn't drowning out your piano.
• Notes are detected late or early. Try a faster detection model (Standard), or lower the playback Speed so you have more time per note.
• No sound / no notes falling. Confirm the MIDI file loaded — the header should no longer read "No file loaded." Press Space to start.
• Wrong hand is highlighted. Re-check the Hand selector; it applies to the whole session.

Once calibration is done, it's worth running one short piece in Watch Mode first to confirm the notes and sheet music line up with what you're seeing, then switching to Play Along for scoring.