Automation and triggers Updated November 2026

UrlFetchApp

Q: Is UrlFetchApp asynchronous?

No, fetch blocks until the response arrives. For many requests, use fetchAll, which runs them in parallel and returns all responses at once.

Q: How do I send form data instead of JSON?

Pass payload as a plain object ({a: 1, b: 2}) without contentType; Apps Script encodes it as application/x-www-form-urlencoded.

Q: What is the quota?

20,000 UrlFetch calls per day on free accounts and 100,000 on Workspace, with a 50 MB response limit per call.

UrlFetchApp.fetch(url, options) makes a synchronous HTTP request and returns a response: response.getContentText() for the body and getResponseCode() for the status. Pass {method: "post", contentType: "application/json", payload: JSON.stringify(data), headers: {Authorization: "Bearer ..."}, muteHttpExceptions: true} for a JSON POST. Parse with JSON.parse.

Syntax

UrlFetchApp.fetch(url, {method, headers, contentType, payload, muteHttpExceptions})

Part	What it is
`method`	get (default), post, put, patch, delete
`headers`	Object of header names to values, for example Authorization
`payload`	Request body; a string (JSON) or an object (form-encoded)
`muteHttpExceptions`	true to get the response for 4xx and 5xx instead of a thrown error
`UrlFetchApp.fetchAll(requests)`	Run many requests in parallel; array of {url, ...options}

Examples

const res = UrlFetchApp.fetch("https://api.exchangerate.host/latest?base=USD");
const data = JSON.parse(res.getContentText());
Logger.log(data.rates.EUR);

Result: A number such as 0.92 (the EUR rate in the response)

const options = {
  method: "post",
  contentType: "application/json",
  headers: {Authorization: "Bearer " + PropertiesService.getScriptProperties().getProperty("API_KEY")},
  payload: JSON.stringify({name: "Ana", email: "ana@example.com"}),
  muteHttpExceptions: true
};
const res = UrlFetchApp.fetch("https://api.example.com/contacts", options);
Logger.log(res.getResponseCode() + " " + res.getContentText());

Result: 201 {"id":123,"name":"Ana"} (or the error body with its code instead of an exception)

const items = JSON.parse(UrlFetchApp.fetch(url).getContentText());
const rows = items.map(it => [it.id, it.name, it.price]);
sheet.getRange(2, 1, rows.length, 3).setValues(rows);

Result: API records written as rows with id, name and price

const reqs = ids.map(id => ({url: "https://api.example.com/items/" + id, muteHttpExceptions: true}));
const responses = UrlFetchApp.fetchAll(reqs);
Logger.log(responses.map(r => r.getResponseCode()));

Result: [200, 200, 404] (one code per request, fetched in parallel)

Common mistakes

Exception: Request failed for ... returned code 401: the API key or token is missing or wrong; put it in Script Properties and send it in the header the API expects.
The API receives an empty body: you passed an object as payload without contentType application/json, so it was form-encoded; use JSON.stringify and set contentType.
Unexpected token < in JSON: the response is HTML (an error page or login page); log getContentText and getResponseCode before parsing.
Address unavailable or blocked: UrlFetchApp cannot reach localhost or private networks; the API must be public on the internet.

Practice UrlFetchApp

These drills check your answer on live data, free, no account needed.

Retry a failing callCall `fn()` until it succeeds, at most `attempts` times, and resolve with its result. `fn` may return a Promise or a plain value, and it may throw or reject. If every attempt fails, reject with the error from the last attempt.
Promise.all with a concurrency limitLike `Promise.all(items.map(fn))`, but with at most `limit` calls of the async function `fn(item)` running at the same time. Resolve with the results in the order of `items`. Start the next item as soon as any running one finishes. If a call rejects, reject. Tests run on a fake clock: `setTimeout`, `clearTimeout` and `Date.now` are simulated, so waits are instant and exact.
Timeout wrapperReturn a Promise that settles like `promise` if it settles within `ms` milliseconds. Otherwise reject with `new Error("Timed out")` at `ms`. Clear your timer once the result is known, so nothing is left pending. Tests run on a fake clock: `setTimeout`, `clearTimeout` and `Date.now` are simulated, so waits are instant and exact.

Questions

Is UrlFetchApp asynchronous?