Why is my phone camera blurry all of a sudden?

A camera that has suddenly gone soft is almost never a failed sensor. It is nearly always something on the outside of the lens or something in front of it.

Safety

Step by step

1. Clean the lens properly.A microfibre cloth, dry, in small circles. Fingerprints and pocket grease are the cause in most cases and they are invisible against a dark lens. Do this before anything else.
2. Do not use anything abrasive.Tissue, kitchen roll, a shirt and glasses wipes with alcohol can all damage the coating. A microfibre cloth, and a drop of lens cleaner on the cloth if it is really greasy.
3. Check the case.A case that overlaps the lens slightly, or a screen protector film left over the camera, softens the image and causes odd flare. Take the case off and retest.
4. Look for condensation inside.A misty appearance that does not wipe off is moisture behind the lens cover. Leave the phone somewhere warm and dry for a day. Rice is unnecessary and largely a myth.
5. Test each lens separately.Modern phones have several. Switch between the wide, ultrawide and telephoto — if only one is soft, that narrows it immediately and rules out software.
6. Tap to focus.Autofocus hunting on a low-contrast subject or in poor light produces a soft image. Tapping the subject forces it, and it confirms whether focus is the problem.
7. Check for a stuck autofocus.A faint rattle when the phone moves is normal on some models. Persistent buzzing with a permanently soft image suggests the focus mechanism, which is a repair.
8. Restart the phone.Camera apps occasionally hang in a state where focus or stabilisation stops working. A restart resolves a genuine proportion of sudden camera faults.
9. Rule out the app.Try the built-in camera app rather than a social media one. In-app cameras are usually lower quality and are a common reason photos look worse than expected.
10. Consider magnetic damage.Strong magnets — some car mounts and accessories — can disturb optical image stabilisation permanently. If it started after using one, that is a likely cause.
11. Check for a cracked lens cover.Hold it at an angle in good light. A hairline crack in the cover glass scatters light and softens everything. The cover is replaceable independently of the camera on many models.
12. Clear the camera app cache.On Android, clearing the camera app's cache resolves some persistent focus and processing faults without losing anything.

Tips

• Clean the lens first, always. It is the cause far more often than everything else combined.
• Test each lens separately. If only one is soft, it is hardware and you have already narrowed it.
• Microfibre only. Tissue and shirts scratch the coating and make it permanent.

Common mistakes

• Cleaning the lens with tissue or a shirt — Both are abrasive enough to scratch the lens coating, which turns a temporary smear into permanent softness.
• Assuming the camera has failed — Sensors rarely fail. Grease, a case edge, condensation and focus problems account for nearly every sudden case.

If it doesn't work