How do I open a stuck jar?
Five methods in order of effort, starting with the one that works most of the time.
- Difficulty
- beginner
- Time
- 3 min
- Read
- 2 min
Short answer
Tap the edge of the lid firmly around its circumference with the back of a spoon, then try again. That breaks the vacuum seal and opens most jars. If not, run hot water over the lid for thirty seconds — metal expands more than glass.
A stuck jar is usually held by a vacuum rather than by friction. Break the seal and the lid turns freely. That is why tapping works and why brute force so often does not.
What you'll need
- Spoon (optional)
- Rubber glove or elastic band (optional)
- Hot water (optional)
Step by step
- Tap firmly around the edge of the lid with the back of a spoon.Six or eight taps all the way round. It deforms the lid slightly and lets air in, breaking the vacuum. This alone opens most jars.
- Improve your grip.A rubber glove, a wide elastic band round the lid, or a dry tea towel. Most failed attempts are the hand slipping rather than a lack of strength.
- Run hot water over the lid for thirty seconds.Metal expands more than glass, so the lid loosens on the jar. Keep the water off the glass to avoid thermal shock.
- Slide a spoon or blunt knife under the lid's edge and lever gently.You will often hear the seal give. Gentle is the operative word — forcing it can chip the glass rim.
- Grip the jar low and turn the lid, not the jar.Hold the jar against your body for leverage. Turning both at once wastes most of your effort.
- Use a jar opener or the underside of a drawer handle for leverage.A V-shaped opener grips the lid and multiplies force considerably. Some drawer handles work as an improvised one.
- If nothing works, pierce the lid.A small hole with a can opener point releases the vacuum instantly. It ruins the reseal, so it is a last resort for a jar you will finish.
Tips
- Wet or greasy hands are the most common reason a jar 'will not open'. Dry everything first and try again before escalating.
- Storing jars with the lids very slightly loose after first opening prevents them sticking again.
- If a jar lid is bulging or hisses violently when opened, discard the contents — that indicates fermentation and spoilage.
Common mistakes
- Applying more force with a slipping grip — You are losing the effort to slip, not to the lid. A rubber glove or tea towel solves it instantly.
- Running very hot water over the glass as well — Thermal shock can crack the jar. Direct the water at the metal lid only.
- Levering hard with a knife — It chips the glass rim, and glass fragments in food are a genuine hazard. Gentle leverage only.
Questions people ask
Why does tapping a jar lid help it open?
It deforms the lid very slightly and lets air past the seal, releasing the vacuum that is holding it shut. Once the vacuum breaks, the lid usually turns freely.
Does hot water really loosen a jar lid?
Yes. Metal expands more than glass when heated, so thirty seconds of hot water on the lid enlarges it relative to the jar. Keep the water off the glass.