ECONNABORTED error when Axios request times out

The ECONNABORTED error Axios emits when a request timeout expires is well-documented, but the exact moment the timeout counter begins varies by environment.

Likely explanation

In browsers, the timeout timer is set to fire immediately after axios.request() is invoked, before the request body finishes queuing for transmission. The timer drives an AbortController that aborts the underlying XHR/fetch, producing ECONNABORTED. In Node.js, Axios maps the timeout to http.request's timeout option; the same immediate-start pattern applies, aborting the socket after expiry.

Confirmed facts

• Timeout starts at request initiation, not after body transmission completes.
• When the timeout fires before a response arrives, the promise rejects and validateStatus is generally bypassed.
• If a response arrives milliseconds after the timer fires, the rejection may already have occurred, so validateStatus may not be invoked.

Version-dependent behavior

Older Axios versions used a setTimeout wrapper around the XHR loadstart event, while newer versions prefer the AbortController pattern. The start-moment semantics have not changed, but the abort mechanism does.

Practical verification

// Verify timeout start moment in browser console
const start = Date.now()
axios.request({ url: '/api', timeout: 1000 })
  .then(r => console.log('resolved', Date.now() - start))
  .catch(e => console.log('rejected', e.name, Date.now() - start))

Inspect the returned AbortController signal or the XHR timeout property after the request; a non-zero value confirms the timer was active before send.

Missing diagnostic detail: What Axios version are you using, and approximately how large is the request body? This helps determine whether version-specific timing quirks or body-upload race conditions are at play.