Fact Check-Microwaving a penny is dangerous, prank online taken seriously

Users are sharing posts that claiming microwaving a penny coin (one U.S. cent) for one minute will make it shrink. This is false and dangerous, as metal objects in a microwave can cause damage or catch on fire.

Examples can be seen here and here with comments including: “Don’t try this at work it you want to keep your job”, “Don't do this... It will destroy your microwave, possibly cause a fire. Don't,” and “Don't try it I just had an explosion”.

The text in one post shows a miniature penny next to a regular one and includes the text: “microwave a penny for 1 minute to get a mini coin.”

Most posts are shared by meme pages as satire, but users who have tried it have had dangerous results, visible here and here .

Pennies are made from zinc coated with copper, as explained here and here . Copper is a conductor of heat and electricity, which makes it unsafe to place in a working microwave (here).

MIT’s School of Engineering explains in a post here that microwaves are a type of electromagnetic radiation similar to radio waves. The microwaves bounce around inside the oven when turned on and are absorbed by food’s water content, which allows it to heat up.

However, a metal object in the oven deflects the waves causing them to bounce around erratically and potentially damage the microwave, according to the blog post.

Videos showing what happens when coins, including pennies, are microwaved can be seen here and here .

There is no evidence that microwaving a penny will cause it to shrink. Miniature pennies are available for purchase from online retailers, usually as a part of a magic trick, as seen here .


False. Microwaving a penny will not cause it to shrink but could potentially damage the microwave.

This article was produced by the Reuters Fact Check team. Read more about our fact-checking work  here  .