Crocheting circles is easy with these free tutorials and patterns.
Erica Jackofsky put together this detailed tutorial for how to crochet in the round. If you grab a some cotton yarn and practice along with her, you'll be able to crochet an easy round coaster by the time you're finished the tutorial. Make a few more coasters for even more practice, and then you'll have a complete set to use, and you'll have gained a valuable skill at the same time.
If you just want a quick, beginner-friendly little circle without any increases, this one is a great pattern to try. It's comprised of easy chain stitches and double crochet stitches. My finished circle measures about 1 5/8 inches using medium weight yarn; the size of yours will vary depending on the materials you use.
Please note: I combined multiple circles, along with some metal bottle caps, to create a snowflake-shaped trivet. This tutorial is part of the instructions showing you how to make the entire trivet. Please feel free to make a trivet with the circles if you like, but of course you can use the circles in plenty of other ways too.
Not all circles are crocheted in the round, although it's an easy and intuitive way to build a circle shape.
This round design is crocheted in rows, with increases and decreases creating the shaping. A heart motif is the focal point of the design.
Sandi Marshall has also posted a free pattern for crocheting a basic flat circle. She wrote a couple of additional pages you might also find helpful: