# How do you know if a bike is the right size? Canonical: https://zestasy.com/wiki/right-bike-size/ Section: Zestasy Wiki > Movement · Updated: 2026-10-14 · Publisher: Zestasy *Zestasy Wiki: our reference answers. Checked for facts and sources; less curated than the magazine.* A bike is the right size if you can stand over the frame with both feet flat on the ground, reach the handlebars with a slight bend in your elbows and without stretching, and set the saddle so your leg is nearly straight at the bottom of the pedal stroke without your hips rocking. Size charts are a starting point; a test ride tells you far more, and a professional fit is worth it if you ride a lot or something keeps feeling wrong. A bike that fits disappears beneath you. A bike that does not fit nags at you all the way: stretched shoulders, numb hands, knees up by your ears. The good news is that fit is easy to check with a few simple tests, and a lot can be adjusted after you buy. ## Start with the size chart, then ignore it a bit Manufacturers publish size charts based on height and sometimes inside-leg length. They are useful for narrowing down to one or two sizes. They are not the final word, because frame shapes vary between brands and between types of bike, and two people of the same height can have very different leg and arm lengths. Use the chart to choose what to test ride. ## Check one: standover Stand over the bike, in front of the saddle, with both feet flat on the ground. You should have some clearance between you and the top tube. On bikes with a sloping or very low top tube, such as many city and step-through bikes, this is rarely an issue. If you cannot stand over it comfortably, it is too big. ## Check two: saddle height Saddle height is adjustable on every bike, but the frame has to let you get it right. Cycling UK's method: 1. Sit on the bike (lean it against a wall or have someone hold it) wearing your usual shoes. 2. Put your heel on the pedal and turn the cranks back until the pedal is at the bottom. 3. With your heel on the pedal, your leg should be straight. When you then ride with the ball of your foot on the pedal, your knee keeps a slight bend at the bottom. 4. If your hips rock from side to side as you pedal, the saddle is too high. Cycling UK notes that many people ride with the saddle set far too low, and that beginners may prefer it a little lower at first. It also suggests keeping the saddle level. If you cannot get the saddle to the right height because the seat post runs out, or because the saddle can't go low enough, the frame is the wrong size. ## Check three: reach Reach is the distance from the saddle to the handlebars. Sitting on the saddle with your hands on the bars, you should feel relaxed: - **Elbows slightly bent,** not locked straight. - **Shoulders loose,** not hunched up by your ears. - **No sense of stretching** to reach the brakes or gears. Cycling UK explains that reach can be fine-tuned by moving the saddle forward or back a little, or by changing the stem, although a longer stem makes steering feel slower. Small adjustments are normal; a bike that needs huge ones is probably the wrong size. ## The test ride tells the truth Nothing replaces riding it. On a test ride: - **Ride for longer than once round the car park** if the shop allows it. - **Try standing up on the pedals,** turning tightly and braking hard. - **Check you can reach the floor** when you stop, by tipping the bike or sliding forward off the saddle. - **Notice your hands, neck and back.** Pressure or strain after a few minutes will be worse after an hour. - **Compare two sizes back to back** if you are between them. If you are between sizes, the general instinct is that a smaller frame is easier to adjust upwards than a larger frame is to shrink, but your test ride should decide. ## When a professional fit is worth it A bike fit is a session with a trained fitter who adjusts the bike to you. It is worth considering if: - you ride long distances or often, - you are buying an expensive bike and want to choose the size before you buy, - or you have discomfort that small adjustments have not solved. For most people riding to work or on weekends, the three checks above and a good bike shop are enough. Our guide to a [comfortable saddle](https://zestasy.com/wiki/comfortable-saddle/) handles the next most common complaint. ## FAQ ### Can I just go by my height? Height gets you into the right range, but leg and arm length vary. Use height to shortlist sizes and a test ride to choose. ### What if I'm between two sizes? Ride both. Many people find the smaller one more nimble and easier to adjust with a longer stem or seat post, but it depends on the bike and on you. ### Is a second-hand bike worth buying if it's slightly the wrong size? A little off can be fixed with a different stem, seat post or saddle position. A lot off cannot, however good the bargain. ### Do kids' bikes work the same way? The same idea applies: they should be able to stand over the bike and reach the ground. Children grow fast, but a bike that is too big is harder to control; see our guide to [cycling with kids](https://zestasy.com/wiki/cycling-with-kids/). ## Sources - [Cycling UK: How to make your bike more comfortable](https://www.cyclinguk.org/node/23801) - [Cycling UK: Video guide: how to set the correct saddle height](https://www.cyclinguk.org/article/video-guide-how-set-correct-saddle-height) ## Related - [What is the difference between a road bike, a gravel bike and a hybrid?](https://zestasy.com/wiki/road-gravel-hybrid/) - [How do you make a bike saddle more comfortable?](https://zestasy.com/wiki/comfortable-saddle/) - [What kind of bike is best for getting around town?](https://zestasy.com/wiki/city-bike/) - [How do you start cycling to work?](https://zestasy.com/movement/start-cycling-to-work/) - [What bike maintenance can you do yourself?](https://zestasy.com/wiki/basic-bike-maintenance/) - [All Movement answers in the Wiki](https://zestasy.com/wiki/#movement)