Summarizer: inputQuota property

Limited availability

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

See full compatibility

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 Summarizer interface returns the input quota available to the browser for generating summaries.

Value

A number specifying the available input quota. This number is implementation-dependent. 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.

Examples

Checking if you have sufficient quota

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

We then test to see if the individual input usage for that string is great than the total available quota. If so, we throw an appropriate error; it not, we commence summarizing the string using summarize().

const summarizer = await Summarizer.create({
  sharedContext:
    "A general summary to help a user decide if the text is worth reading",
  type: "tldr",
  length: "short",
});

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

if (inputUsage > totalInputQuota) {
  throw new Error("Boo, insufficient quota to generate a summary.");
} else {
  console.log("Yay, quota available to generate a summary.");
  const summary = await summarizer.summarize(myTextString);
  // ...
}

Specifications

Specification
Writing Assistance APIs # dom-summarizer-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 138 (Release date: 2025-06-26) disabled disabled From version 138 users must explicitly set the `#edge-llm-summarization-api-for-phi-mini` preference to `Enabled`. To change preferences in Edge, visit about:flags.	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

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.
: User must explicitly enable this feature.