Measure your height
To help find the right size bike you will need to measure both your height and your inside leg.
For your height:
Stand against a wall and mark the wall with a pencil so it's level with the top of your head. Then measure from the ground up to the mark (having someone to help might make this easier). For your inside leg measurement, stand against a wall and using a book hold it in between your legs tucked into your groin and make sure it's flat against the wall. Measure the height from the floor to the book. (Again it might be easier and more fun to get a friend to help).
If your height falls on the cusp of the stated size range, your reach will be the deciding factor in which size you go for. To work out what sort of reach you have you will need to measure your “Ape Index”. This is your arm span deducted from your height. If you have a positive ape index then it means you’re better going for the larger size, but if you have a negative ape index go for a smaller size.
The type of bike
The type of bike you choose and your style of riding will affect the size of bike that you buy. For example, a mountain biker that rides aggressively, shredding gnar, may want something more manoeuvrable so could prefer a size smaller than they would normally take. Similarly, a cross country racer that is looking for something of a flatter and speedier mountain bike might prefer a size larger than they would normally take.
There is no definitive right or wrong size, it all comes down to your personal preference and what feels comfortable for you.
How bikes are measured
Bikes are usually measured by their seat tube length. This measurement is normally either from the centre of the bottom bracket (BB) or the centre of the bolt that attachs the crank arms.
This can differ by brand, some of them measure to the top of where the top tube meets the seat tube, or even the centre of the top tube. Which is why this guide should only be treated as a rough idea to sizing. Check with one of our experienced staff for a better, more accurate fit.
Mountain bikes are either measured in inches or descriptive sizes (small, medium etc). Road bikes are in centimetres or descriptive sizes where as Hybrid bikes can be any one of the three. Bikes also get longer as they go up in size (relative to the frame size) but different brands can be inherently longer or shorter than others.
Children's bikes are measured by wheel size.
Stand over height
Stand over height: this is how tall the frame is from the ground. Stand over height measurements are to the top of the top-tube. Ideally you want at least 2cm of clearance between you and the frame. In theory your stand over height is your inside leg measurement minus 2cm. By measuring your inside leg with your shoes on you can establish your stand over height. In the case that you need to jump off the saddle quickly, the clearance between you and the frame should prevent any injuries.
Most road bikes come in two styles – racing road bikes (long in the top tube and low at the front for faster riding) and sportive road bikes (which tend to have shorter top tubes and higher front ends for extra comfort). In recent years there's also been a rise in cyclocross bikes, which are for more casual off road rides, and that’s led to the creation of adventure road bikes – a lightweight, drop-bar bike for a mix of terrains, roads and trails. For more information on road bikes and adventure road bikes visit our buying guide.
RIDER HEIGHT
4'10" - 5'0"
5'0" - 5'3"
5'3" - 5'6"
5'6" - 5'9"
5'9" - 6'0"
6'0" - 6'3"
6'3" - 6'6"
SUGGESTED FRAME SIZE
XX-Small (47cm - 48cm)
X-Small (49cm - 50cm)
Small (51cm - 53cm)
Medium (54cm - 55cm)
Large (56cm - 58cm)
X-Large (58cm - 60cm)
XX-Large (61cm - 63cm)
RIDER HEIGHT
148cm - 152cm
152cm - 160cm
160cm - 168cm
168cm - 175cm
175cm - 183cm
183cm - 191cm
191cm - 198cm
SUGGESTED FRAME SIZE
XX-Small (47cm - 48cm)
X-Small (49cm - 50cm)
Small (51cm - 53cm)
Medium (54cm - 55cm)
Large (56cm - 58cm)
X-Large (58cm - 60cm)
XX-Large (61cm - 63cm)
Many bikes are designed with the female form in mind. So they accommodate a shorter reach, narrower shoulders and smaller hands. But there’s absolutely no reason why a woman can’t ride a unisex or male bike, so don’t restrict yourself – just make sure you test ride it first.
RIDER HEIGHT
4'10" - 5'1"
5'1" - 5'3"
5'3" - 5'5"
5'5" - 5'8"
5'8" - 5'10"
SUGGESTED FRAME SIZE
XX-Small (44cm - 46cm)
X-Small (47cm - 49cm)
Small (50cm - 52cm)
Medium (53cm - 55cm)
Large (56cm - 57cm)
RIDER HEIGHT
147cm - 155cm
155cm - 160cm
160cm - 165cm
165cm - 172cm
172cm - 180cm
SUGGESTED FRAME SIZE
XX-Small (44cm - 46cm)
X-Small (47cm - 49cm)
Small (50cm - 52cm)
Medium (53cm - 55cm)
Large (56cm - 57cm)
Women’s MTBs tend to be shorter in length, have narrower handlebars and smaller frame sizes. They also have specific saddles and often have their own colour scheme too. Like other MTBs, these designs are measured in the same way (from the centre of the bottom bracket to the top of the seat tube) but there’s no reason why you shouldn’t try a unisex MTB.
RIDER HEIGHT
4'10" - 5'2"
5'2" - 5'6"
5'7" - 5'9"
5'10" - 6'1"
FRAME SIZE
13" - 14"
15" - 16"
17" - 18"
19"+
RIDER HEIGHT
4'10" - 5'2"
5'2" - 5'6"
5'7" - 5'9"
5'10" - 6'1"
FRAME SIZE
X-Small Bikes
Small Bikes
Medium Bikes
Large Bikes
RIDER HEIGHT
148cm - 158cm
158cm - 168cm
168cm - 178cm
178cm - 185cm
FRAME SIZE
33 - 37
38 - 42
43 - 47
48 +
RIDER HEIGHT
148cm - 158cm
158cm - 168cm
168cm - 178cm
178cm - 185cm
FRAME SIZE
X-Small Bikes
Small Bikes
Medium Bikes
Large Bikes
RIDER HEIGHT
4'10" - 5'2"
5'2" - 5'6"
5'6" - 5' 10"
5'10" - 6'1"
6'1" - 6'4"
6'4" - 6'6"
FRAME SIZE
13" - 14"
15" - 16"
17" - 18"
19" - 20"
21" - 22"
23" - 24"
RIDER HEIGHT
148cm - 158cm
158cm - 168cm
168cm - 178cm
178cm - 185cm
185cm - 193cm
193cm - 198cm
FRAME SIZE
33 - 37
38 - 42
43 - 47
48 - 52
53 - 57
58 - 61
RIDER HEIGHT
4'10" - 5'2"
5'2" - 5'6"
5'6" - 5' 10"
5'10" - 6'1"
6'1" - 6'4"
6'4" - 6'6"
FRAME SIZE
13" - 14"
15" - 16"
17" - 18"
19" - 20"
21" - 22"
23" - 24"
RIDER HEIGHT
4'10" - 5'2"
5'2" - 5'6"
5'6" - 5' 10"
5'10" - 6'1"
6'1" - 6'4"
6'4" - 6'6"
FRAME SIZE
X-Small Bikes
Small Bikes
Medium Bikes
Large Bikes
X-Large Bikes
XX-Large Bikes
RIDER HEIGHT
148cm - 158cm
158cm - 168cm
168cm - 178cm
178cm - 185cm
185cm - 193cm
193cm - 198cm
FRAME SIZE
33 - 37
38 - 42
43 - 47
48 - 52
53 - 57
58 - 61
RIDER HEIGHT
148cm - 158cm
158cm - 168cm
168cm - 178cm
178cm - 185cm
185cm - 193cm
193cm - 198cm
FRAME SIZE
X-Small Bikes
Small Bikes
Medium Bikes
Large Bikes
X-Large Bikes
XX-Large Bikes
Women's hybrids differ to male/unisex hybrids. They tend to be shorter in length with narrower handlebars and smaller frame sizes. In some cases they’ll have a step through frame where the top tube drops down, meeting the seat tube much lower. In some cases a male/unisex hybrid may suit you better.
RIDER HEIGHT
4'10" - 5'2"
5'2"" - 5'6""
5'6" - 5' 10"
5'10" - 6'1"
FRAME SIZE
13" - 14"
15" - 16"
17" - 18"
19"+
RIDER HEIGHT
148cm - 158cm
158cm - 168cm
168cm - 178cm
178cm - 185cm
FRAME SIZE
X-Small Bikes
Small Bikes
Medium Bikes
Large Bikes
RIDER HEIGHT
4'10" - 5'2"
5'2" - 5'6"
5'6" - 5' 10"
5'10" - 6'1"
6'1" - 6'4"
6'4" - 6'6"
FRAME SIZE
13" - 14"
15" - 16"
17" - 18"
19" - 20"
21" - 22"
23" - 24"
RIDER HEIGHT
148cm - 158cm
158cm - 168cm
168cm - 178cm
178cm - 185cm
185cm - 193cm
193cm - 198cm
FRAME SIZE
33 - 37
38 - 42
43 - 47
48 - 52
53 - 57
58 - 61
RIDER HEIGHT
148cm - 158cm
158cm - 168cm
168cm - 178cm
178cm - 185cm
185cm - 193cm
193cm - 198cm
FRAME SIZE
X-Small Bikes
Small Bikes
Medium Bikes
Large Bikes
X-Large Bikes
XX-Large Bikes
Women's hybrids differ to male/unisex hybrids. They tend to be shorter in length with narrower handlebars and smaller frame sizes. In some cases they’ll have a step through frame where the top tube drops down, meeting the seat tube much lower. In some cases a male/unisex hybrid may suit you better.
RIDER HEIGHT
4'10" - 5'2"
5'2"" - 5'6""
5'6" - 5' 10"
5'10" - 6'1"
FRAME SIZE
13" - 14"
15" - 16"
17" - 18"
19"+
RIDER HEIGHT
4'10" - 5'2"
5'2"" - 5'6""
5'6" - 5' 10"
5'10" - 6'1"
FRAME SIZE
X-Small Bikes
Small Bikes
Medium Bikes
Large Bikes
RIDER HEIGHT
148cm - 158cm
158cm - 168cm
168cm - 178cm
178cm - 185cm
FRAME SIZE
X-Small Bikes
Small Bikes
Medium Bikes
Large Bikes
RIDER HEIGHT
4'10" - 5'2"
5'2" - 5'6"
5'6" - 5' 10"
5'10" - 6'1"
6'1" - 6'4"
6'4" - 6'6"
FRAME SIZE
13" - 14"
15" - 16"
17" - 18"
19" - 20"
21" - 22"
23" - 24"
RIDER HEIGHT
4'10" - 5'2"
5'2" - 5'6"
5'6" - 5' 10"
5'10" - 6'1"
6'1" - 6'4"
6'4" - 6'6"
FRAME SIZE
X-Small Bikes
Small Bikes
Medium Bikes
Large Bikes
X-Large Bikes
XX-Large Bikes
RIDER HEIGHT
148cm - 158cm
158cm - 168cm
168cm - 178cm
178cm - 185cm
185cm - 193cm
193cm - 198cm
FRAME SIZE
33 - 37
38 - 42
43 - 47
48 - 52
53 - 57
58 - 61
Women’s MTBs tend to be shorter in length, have narrower handlebars and smaller frame sizes. They also have specific saddles and often have their own colour scheme too. Like other MTBs, these designs are measured in the same way (from the centre of the bottom bracket to the top of the seat tube) but there’s no reason why you shouldn’t try a unisex MTB.
RIDER HEIGHT
4'10" - 5'2"
5'2"" - 5'6""
5'6" - 5' 10"
5'10" - 6'1"
FRAME SIZE
13" - 14"
15" - 16"
17" - 18"
19"+
RIDER HEIGHT
148cm - 158cm
158cm - 168cm
168cm - 178cm
178cm - 185cm
FRAME SIZE
X-Small Bikes
Small Bikes
Medium Bikes
Large Bikes
RIDER HEIGHT
4'10" - 5'0"
5'0" - 5'3"
5'3" - 5'6"
5'6" - 5'9"
5'9" - 6'0"
6'0" - 6'3"
6'3" - 6'6"
FRAME SIZE
XX-Small
X-Small
Small
Medium
Large
X-Large
XX-Large
RIDER HEIGHT
148cm - 152cm
152cm - 160cm
160cm - 168cm
168cm - 175cm
175cm - 183cm
183cm - 191cm
191cm - 198cm
FRAME SIZE
47cm - 48cm
49cm - 50cm
51cm - 53cm
54cm - 55cm
56cm - 58cm
58cm - 60cm
61cm - 63cm
Many bikes are designed with the female form in mind. So they accommodate a shorter reach, narrower shoulders and smaller hands. But there’s absolutely no reason why a woman can’t ride a unisex or male bike, so don’t restrict yourself – just make sure you test ride it first.
RIDER HEIGHT
4'10" - 5'1"
5'1" - 5'3"
5'3" - 5'5"
5'5" - 5'8"
5'8" - 5'10"
FRAME SIZE
XX-Small
X-Small
Small
Medium
Large
RIDER HEIGHT
147cm - 155cm
155cm - 160cm
160cm - 165cm
165cm - 172cm
172cm - 180cm
FRAME SIZE
44cm - 46cm
47cm - 49cm
50cm - 52cm
53cm - 55cm
56cm - 57cm
RIDER HEIGHT
147cm - 155cm
155cm - 160cm
160cm - 165cm
165cm - 172cm
172cm - 180cm
FRAME SIZE
XX-Small
X-Small
Small
Medium
Large
How are electric HYBRID bikes measured?
Hybrid bikes are measured from the centre of the bottom bracket (BB) to the top of the seat tube. You might find however that some hybrid manufacturers will measure their bikes slightly differently, depending on the style of the bike. Don't forget you'll need your height and your inside leg measurement. Hybrid bikes are typically sized in S, M, L and XL but there are some models that are sized in inches. This will vary depending on the brand. Always check the manufacturers measurements or visit a store to speak to a experienced member of staff.
How are electric MTBs measured?
MTB's are measured from the centre of the bottom bracket (BB) to the top of the seat tube. To give a rider more stand over height, MTB top tubes often slope down and join the seat tube lower than road bikes. So it’s worth taking your inside leg measurement and comparing it to the manufacturers model. Always check the manufacturer’s measurements or visit a store to speak to an experienced member of staff.
How are electric ROAD bikes measured?
Road bike manufacturers measure their bikes slightly differently. Some will measure centre of the BB to the top of the top tube (centre to top) or centre of the BB to the centre of the top tube (centre to centre). And bear in mind that a lot of road bikes have sloping top tubes so the measurements can alter – these are often sized S, M, L and XL