#1189: Incubation: Web Speech API: On-Device Recognition Quality

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Opened Feb 2, 2026

Explainer

https://github.com/WebAudio/web-speech-api/blob/main/explainers/quality-levels.md

The explainer

Where and by whom is the work is being done?

  • GitHub repo: https://github.com/WebAudio/web-speech-api/
  • Primary contacts: Evan Liu (evliu@google.com), Google, Author
  • Organization/project driving the design: Google Chrome
  • This work is being funded by: Google
  • Incubation and standards groups that have discussed the design: Audio WG, TPAC 2025
  • Standards group(s) that you expect to discuss and/or adopt this work when it's ready: Audio WG

Feedback so far

You should also know that...

Summary: Extends the SpeechRecognition interface by adding a 'quality' property to SpeechRecognitionOptions. This allows developers to specify the semantic capability required for on-device recognition (via processLocally: true). The proposed quality enum supports three levels: 'command', 'dictation', and 'conversation'.

Specification URL: https://webaudio.github.io/web-speech-api

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Discussions

Discussed Feb 2, 2026 (See Github)

Christian and Matthew are assigned.

Discussed Feb 9, 2026 (See Github)

Christian: Marcos mentioned this has the same issue as PromptAPI, you can query if there is a model present on the device suitable for a certain level/language, this could be a fingerprint vector. I want to reccomend they look at Prompt API review.

Ehsan: Isn't this the same problem with all language based models? Maybe we can have a consistent answer.

Lola: Do you suggest we should have a document on language-based models?

Ehsan: That would be my suggestion. Come up with a document that describes all of that. Should be done at the WebML groups. Think this is coming up more often.

Marcos: It’s a more general problem of downloading system components which then you can query, because then they become global.

Lola: To make this even more general, should we have a position on downloading system components? Or is this restricted to this use case?

Marcos: No, could be related to everything. Codecs, etc. Should be a design principle.

Lola: Who would be willing to write that? We also have another plenary before the F2F.

Christian: Could offer to do that, would be my first design principle, and a topic where I’m interested in.

Ehsan: Same here. Would be good to have a more experienced TAG member on that as well.

Lola: Design principles is owned by Jeffrey, so we can talk to him about that.

Comment by @christianliebel Feb 19, 2026 (See Github)

Hi @evanbliu, thank you for your proposal.

We have one question regarding privacy: Could an attacker fingerprint the user’s browsing history by installing certain or rare languages along with model qualities on site A, and checking for the availability of those permutations on site B? And if so, how is that fingerprinting concern mitigated?

It would be great if you could add a security & privacy questionnaire and answer that question.