This kind of bathroom lock is usually a “privacy” lock that’s designed to be opened from the outside with a small straight tool.
Quick safety note
Make sure no one inside needs medical help or emergency services; if they do, call local emergency services or a locksmith immediately instead of trying multiple forceful methods.
Easiest method: straight tool in hole
Most round knobs with a small round hole in the center open by pushing a release button inside.
- Find a thin, rigid object: straightened paperclip, small flathead eyeglass screwdriver, stiff wire, or a special “privacy key” if you have one.
- Insert it straight into the hole about 1–2 cm (around 0.5–1 inch) until you feel resistance, then press firmly but gently; you should feel or hear a click and then be able to turn the knob.
If it uses a slotted screw inside
Some locks have a tiny flat slot you must turn instead of just pushing.
- Shine a light into the hole; if you see a little horizontal or vertical slot, use the smallest flathead screwdriver or similar flat tip that fits.
- Insert the tool, rotate slowly until it “drops” into the slot, then turn about a quarter turn (usually counterclockwise) until the lock releases and the knob turns freely.
If the hole method fails
If the mechanism is stuck or damaged, you may need another approach.
- Try sliding a flexible plastic card between the latch and frame at the latch height and wiggle/push to retract the latch, if there is a bit of play in the door.
- If you can see screws on the knob, remove them with a screwdriver, pull the knob/rosette off, and manually move the latch to open the door.
When to stop and call a pro
If the door still will not open, or your tools are slipping and scratching the hardware or frame badly, it is better to stop and call a locksmith to avoid breaking the lock or door.