We're a small project called seespeak. A native speaker's phrase loops and its pitch is drawn as a ribbon; you press once, speak along, and your own voice draws over it in another colour on the same clock. Where the ribbons part you see which sound was off, and whether you came early or late.

The link opens on 买 mǎi (buy), which dips and rises; 卖 mài (sell) just falls. Both are said by Levi Highway (CC0, Lingua Libre). Every voice on the page is a real native speaker, credited where it plays: no synthetic voices. There are more Mandarin tone pairs, and English and Russian sentences.

The number on screen is computed only from the two sounds (the pitch lined up by time warping), and shown beside what two natives reach on the same sentence, since even two natives never match fully. It runs in a phone browser with no signup; your recording goes to our server for the sound check and is not kept.

We'd like to hear where it misleads you, or which pairs you'd want next.