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Two Guided Tests

Autofocus Speed & Minimum Focus Distance Test

A live sharpness score tracks your camera's focus in real time using the same edge-detection technique as our screen-share sharpness tool. Two tests run on top of it: how fast your autofocus recovers after something disrupts it, and how far your measured sharpness actually drops when you mark focus as lost while moving closer. No invented distance numbers — real measurements of what your camera is doing.

Camera off

Live

Sharpness Score

Current: (relative units — compare against itself over time, not against another camera's number)

Test 1

Autofocus Recovery Speed

Click Arm, then quickly move something across the frame or bring a new object into the foreground to disrupt focus. Timing starts the moment a drop is detected.

Start the camera first.

Result:

Test 2

Minimum Focus Range Check

Click Start, then slowly bring a textured object — your hand, a business card, anything with visible detail — closer to the camera. Click "Focus Lost Here" the instant it visibly blurs.

Start the camera first.

Result:

Notes

Why these two tests, and not a distance number

Camera-to-subject distance genuinely cannot be measured from a single 2D image without either a calibrated reference object or a second camera for stereo depth — neither of which a typical webcam test page has access to. Rather than fabricate a centimetre figure that would just be wrong, both tests here report what is actually, robustly measurable: elapsed time for the recovery test, and relative sharpness-score change for the sweep test. Both are real signals about your specific camera's behavior.

Reading your results

ReadingRangeWhat it means
Fast recovery< 500 msNear-instant — will not be noticeable on a call.
Moderate recovery500 ms – 1.5 sNoticeable but tolerable, especially for casual calls.
Slow recovery> 1.5 sVisible blur/hunt period on every scene change.
Substantial sweep drop< 40% of peakA real, confirmed loss of focus.
Little to no sweep change> 90% of peakPossibly a fixed-focus lens, not an autofocus fault.

Step-by-Step

How to Run Each Test

  1. Click "Start" and allow camera access when prompted.
  2. For recovery timing: click "Arm Recovery Test," then briefly wave a hand across the lens or change scene depth to disrupt focus, and let it re-lock.
  3. For the sweep test: click "Start Sweep," slowly bring a textured object closer to the camera, and click "Focus Lost Here" the instant it visibly blurs.
  4. Run each test two or three times for a representative reading rather than trusting a single result.

Common Questions

Frequently Asked Questions

Why doesn't this report minimum focus distance in centimetres?
A browser has no way to measure true physical distance without a calibrated reference. Rather than invent a number, this quantifies exactly how much your measured sharpness score drops at the moment you mark focus as lost — a real, honest measurement instead of a fabricated distance.
What counts as a good autofocus recovery time?
Under roughly 500ms feels near-instant on a call. 500ms–1.5s is noticeable but tolerable. Beyond that, viewers will see a visible hunting/blur period every time something in frame changes depth — common on budget webcams under low light, since slower autofocus algorithms are often a cost-cutting measure.
Why does my webcam keep hunting for focus?
Continuous autofocus re-evaluates the scene constantly, and low-contrast or low-light scenes give it less to lock onto, causing visible hunting. Improving lighting is usually the single biggest fix; some webcams also let you switch to a fixed focus distance in their companion software, trading flexibility for stability.
Do all webcams have autofocus?
No — many budget and older webcams use fixed-focus lenses set to be reasonably sharp across a typical desk distance, with no moving parts at all. If your sharpness score barely changes as you move closer or further, that is a sign your camera is fixed-focus rather than autofocus underperforming.
Camera access blocked — how do I fix it?
Click the camera icon in your browser's address bar to confirm this site is allowed, or check your OS's camera privacy settings if the browser already shows it as granted.