A posture reminder Chrome extension works if you spend your whole day in Chrome and leave it open. It stops when Chrome quits, most of the popular ones are timers rather than slouch detectors, and every webcam one on the Chrome Web Store that shows a user count has fewer than 100. A desktop app runs whether or not your browser is open and can watch your posture through the webcam all day.
We make SitApp, which is a desktop app, so we have a stake in this. Every listing, user count and Chrome documentation page below was checked on 19 October 2026.
What posture reminder Chrome extensions do
They fall into two groups.
Timer extensions show a notification every so often, whether or not you’re slouching. The best known is PostureMinder, with about 20,000 users. It was last updated on 29 August 2024. It sends snarky reminders at an interval you set and has no camera. We cover it in our free posture reminder apps roundup.
Webcam extensions use the camera to spot slouching. Several are listed, and the ones that show a user count have fewer than 100:
| Extension | What it does | Users | Last updated |
|---|---|---|---|
| PostureCorrector | Detects slouching and sends desktop notifications | 83 | Nov 2025 |
| StraightenUp AI | Blurs the browser slightly when you slouch | 69 | Apr 2026 |
| StopSlouching | Webcam coaching. The free trial is 3 minutes of detection in total | 7 | May 2026 |
| Posture Alert Studio | You open its sidebar panel and allow camera access | Not shown | Jun 2026 |
With user counts this small, there are few reviews to tell you whether any of them works well.
Where a Chrome extension falls short
It stops when Chrome stops
An extension runs inside Chrome. On Windows and Linux, Chrome has a background mode that keeps it running after you close the last window, and the Chromium policy for that setting lists only those two platforms, with the setting off unless it’s turned on. On a Mac, closing Chrome’s last window leaves it running, but quitting it stops every extension, posture reminders included. If you use Safari, Firefox or Arc for part of the day, a Chrome extension isn’t running then either.
Chrome limits background work
Modern Chrome extensions do their background work in a service worker, and Chrome shuts that down after 30 seconds of inactivity. For timers, extensions use the alarms API, which Chrome limits to once every 30 seconds and “may delay them an arbitrary amount more”. For a reminder every 20 minutes, a short delay doesn’t matter.
Webcam detection runs in a page instead, such as a tab, a side panel or an offscreen document, and an extension can only have one offscreen document open at a time. Posture Alert Studio’s listing, for example, tells you to open its sidebar panel and allow camera access.
Some feedback only works in the browser
StraightenUp AI blurs the browser when you slouch. That works while you’re reading a web page. In a code editor, a spreadsheet or the Zoom app, nothing blurs. If much of your day happens outside Chrome, check what the extension does to get your attention there.
Some detection is basic
When one developer shared their posture extension on Hacker News, they explained that it tracked only how far your right eye moved up or down from a baseline, and described it as an occasional reminder they turned on while browsing.
What a desktop posture app does differently
A desktop app runs on its own, separate from any browser. It sits in the menu bar or system tray, can start when you log in, and keeps working whether you’re in Chrome, Word, Figma or a terminal. You grant camera access once, and nothing needs to stay open in a browser.
SitApp works this way on Mac, Windows and Linux. You calibrate it by sitting up straight and then slouching, and from then on it nudges you when you slump. Video is processed on your computer and no images are stored or uploaded. The free plan includes an hour of posture monitoring a day plus break reminders. If you want to know how webcam detection holds up, we wrote about how accurate webcam posture detection is.
A desktop app has downsides. You have to install it, which a locked-down work laptop may not allow, and a Chromebook may leave a browser extension as your only choice. If you only want a gentle timer while you browse, PostureMinder is free and takes seconds to add.
Do posture reminders help at all?
In a 2021 study, 21 healthy young adults typed for an hour twice, once with a wearable biofeedback sensor and once without. With the sensor, their neck flexion and upper-back rounding were significantly lower. The feedback came from a wearable, not a webcam, but it worked the same way, with an alert when posture changed instead of on a timer.
Posture is only part of it. OSHA notes that “working in the same posture or sitting still for prolonged periods is not healthy,” however good that posture is. A tool that also gets you up for movement breaks covers both. For desk setup and other fixes, see how to stop slouching at your desk.
Frequently Asked Questions
Is there a Chrome extension that detects slouching? Yes. PostureCorrector, StraightenUp AI and StopSlouching all use the webcam. Each had fewer than 100 users in October 2026.
Do posture extensions work when Chrome is closed? Not once Chrome has quit. On Windows and Linux, Chrome’s background mode can keep them running after you close every window, if it’s switched on.
Are webcam posture extensions private? It depends where the video is processed. Check the listing and privacy policy for whether video leaves your computer. Our guide to health app privacy covers what to look for.
What’s the best posture reminder for Chrome users? For a timer, PostureMinder. For slouch detection that keeps working outside the browser, a desktop app. Our best posture app comparison covers the options.
Ali @ SitApp
