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Pronunciation assessment, explained for developers

How scoring engines work, how to turn JSON into feedback learners act on, and honest comparisons of the APIs you are likely to shortlist.

Guide

What is a pronunciation assessment API?

What a pronunciation assessment API takes in, what it returns (sentence, word and sound scores), scripted vs unscripted, pricing models, and how to choose one.

5 min read →
Under the hood

How pronunciation scoring works

How an engine turns audio into pronunciation scores: forced alignment, goodness of pronunciation, native-reference calibration and correction decisions.

4 min read →
Mandarin

How to handle tone sandhi in pronunciation scoring

How Mandarin tone sandhi (3-3 → 2-3, 不 before a 4th tone) breaks naive tone scoring, what we measured, and how a scoring API should handle it.

3 min read →
Tutorial

Add pronunciation feedback to your app in an afternoon

Record audio, send it to a pronunciation assessment API from your server, and turn word and sound scores into feedback learners act on. JS and Python code.

5 min read →
Pricing

Pronunciation assessment API pricing, compared

What pronunciation scoring costs at 1,000, 10,000 and 100,000 recordings a month on SpeechSuper, Speechace, Azure and TonePerfect, assumptions included.

3 min read →
Roundup

The best pronunciation assessment APIs in 2026

SpeechSuper, Speechace, Azure AI Speech, ELSA and TonePerfect compared on languages, scoring depth, unscripted support, pricing and privacy for language apps.

3 min read →

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