I learned cycling with on my elder brother's bike. Obviously, that bike was a bit too big for me. I underwent several instances of falls and near-falls. While riding, that feeling of discomfort irritated me all the time. Let me tell you, you won't want to go through that feeling, especially if you are going to ride a bike for the first time. You should purchase a bike only with respect to your height. Age should not be considered as an essential factor. Many a time, children are not of the average height according to their age. Also, most parents have the tendency to buy a bike just a bit bigger for their children, hoping that children will grow with the bike riding and then they would not be required to purchase a new one subsequently. Don't do this! Simply because, if gone out of control, it can be dangerous for your child. And anyway, bikes have good resale values, so it won't pose much of a problem buying a new one. As I said before, the most important aspect while purchasing a bike is the comfort it provides while riding. These are some of the major aspects you need to pay attention to before purchasing a bike.

• When you sit on the bike, you have to check whether the balls of your feet touch the ground, so that you protect your body parts from bruises at times of loss of balance.
• Check if the handle is at an appropriate position for you to hold. Too much of bending or straightened stance can lead to back pain or shoulder pain. So, make sure that you are conveniently placed while holding the handlebars, and the handlebar width is approximately equal to your shoulder width.
• Try standing above the top tube of the bike with both feet on the ground, and make sure that there is at least two-three inches gap between your crotch and the tube to prevent an injury to your organ at times of sudden braking.
• Also, while taking a test drive of the bike, see to it that your leg muscles are completely stretched when you pedal, to avoid any kind of muscle injury.
• Measure your height and inside length of your leg (distance between groin to feet) accurately and use the bike frame size charts given below to determine what exact bike frame size you need.

What Size Road Bike Do I Need Also called a racing bike, a road bike is specifically designed for speed and usage on paved roads. It is constructed as such to have a lower riding position enabling to speed up minimally curbing the flow of air.

Rider Height	Inside Leg	Frame Size Suggested
Feet and Inches	Centimeter	Inches	Centimeter	Inches	Centimeter
5+	152	27 - 29	68.5 - 73.5	18	48
5.1+	155	27 - 29	68.5 - 73.5	18	48
5.2+	157.5	27 - 29	68.5 - 73.5	18	48
5.3+	160	28 - 30	71 - 76	19	50
5.4+	162.5	28 - 30	71 - 76	19	50
5.5+	165	29 - 31	73.5 - 79	20	52
5.6+	167.5	28 - 30	71 - 76	20	52
5.7+	170	28 - 30	73.5 - 76	21	54
5.8+	172.5	30 - 32	76 - 81	21	54
5.9+	175	31 - 33	79 - 84	22	56
5.10+	177.5	30 - 32	76 - 81	22	56
5.11+	180	32 - 34	81 - 87	23	58
6.0+	183	32 - 34	81.5 - 86.5	23	58
6.2+	188	33 - 35	84 - 89	24	60

What Size Mountain Bike Do I Need Mountain bikes are, primarily, sturdy and made for off-the-road use. They are built such that they allow for easy riding on the rough terrains, making it physically less stressful. So, if you are an outdoor person loving to live on the edge and enjoy that racing adrenaline, here is a chart for you to determine ideal size of a mountain bike.

Hardtail and Hardtail Race
Rider Height	Inside Leg	Frame Size Suggested
Feet and Inches	Centimeter	Inches	Centimeter	Inches	Centimeter
4.10+	142+	26 - 28	66 - 71	13	33
5.0+	147+	27 - 29	68.5 - 73.4	14	36
5.2+	152.5+	27 - 29	68.5 - 73.5	15	38
5.4+	162.5+	28 - 30	71 - 76	16	41
5.6+	167.5+	28 - 30	71 - 76	17	43
5.8+	172.5+	29 - 31	73.5 - 78.4	18	46
5.9+	175+	29 - 31	73.5 - 78.5	19	48
5.10+	177.5+	30 - 32	76 - 81	20	51
6.0+	183+	32 - 34	81.5 - 86.5	21	53
6.2+	188+	33 - 35	84 - 89	22	56
6.4+	193+	34 - 36	86.5 - 91.5	23	58

The charts given above will surely help you to determine the size of the bike. But your personal preference is what matters at the end of the day. After taking a test ride, if you are happy, go for that bike. Don't forget to buy a helmet for a safe ride. It is the most essential accessory to have with any bike.