LanguageDetector: inputQuota property

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The inputQuota read-only property of the LanguageDetector interface returns the input quota available to the browser for detecting languages.

Value

A number specifying the available input quota.

This number is implementation-dependant. For example, it might be Infinity if there are no limits beyond the user's memory and the maximum length of JavaScript strings, or it might be a number of tokens in the case of AI models that use a token/credits scheme.

The only guarantee is that inputQuota - measureInputUsage() will be non-negative if there is sufficient quota to detect the text's language.

Examples

Checking if you have enough quota

In the below snippet, we create a new LanguageDetector instance using create(), then return the total input quota via inputQuota and the input quota usage for detecting a particular text string's language via measureInputUsage().

We then test to see if the individual input usage for that string is greater than the total available quota. If so, we throw an appropriate error; it not, we commence detecting the string's language using detect().

js
const detector = await LanguageDetector.create({
  expectedInputLanguages: ["en-US", "zh"],
});

const totalInputQuota = detector.inputQuota;
const inputUsage = await detector.measureInputUsage(myTextString);

if (inputUsage > totalInputQuota) {
  throw new Error("Insufficient quota to detect languages.");
} else {
  console.log("Quota available to detect languages.");
  const results = await detector.detect(myTextString);
  // ...
}

Specifications

Specification
Translator and Language Detector APIs
# dom-languagedetector-inputquota

Browser compatibility

desktop mobile server
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
Deno
Node.js
inputQuota property
Experimental
Chrome – Full support
Chrome 138 (Release date: 2025-06-24)
footnote
footnote Availability may be subject to geographical restrictions.
Edge – No support
Edge
footnote No support
Firefox – No support
Firefox
footnote No support
Opera – Full support
Opera 122 (Release date: 2025-09-11)
footnote
footnote Availability may be subject to geographical restrictions.
Safari – No support
Safari
footnote No support
Chrome Android – No support
Chrome Android
footnote No support
Firefox for Android – No support
Firefox for Android
footnote No support
Opera Android – No support
Opera Android
footnote No support
Safari on iOS – No support
Safari on iOS
footnote No support
Samsung Internet – No support
Samsung Internet
footnote No support
WebView Android – No support
WebView Android
footnote No support
WebView on iOS – No support
WebView on iOS
footnote No support
Deno – No support
Deno
footnote No support
Node.js – No support
Node.js
footnote No support

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support
No support
No support
Experimental. Expect behavior to change in the future.
See implementation notes.

See also