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Kids Bike Helmet Size Chart

A properly fitting helmet is essential for safety and comfort while riding a bicycle. Follow these steps to ensure you select the right size helmet for your child. 

Step 1: Measure Your Head

Nutcase Bike Helmet Measurement ImageUse a flexible measuring tape to measure the circumference of your child's head. Place the tape measure slightly above the ear, across the mid-forehead, and completely around the head, about 1 inch above the eyebrows. If you don't have a measuring tape, use a string and measure it against a ruler.

Step 2: Choose Your Helmet

Consult the size chart below to find the appropriate helmet size based on the head circumference measurement.

Head Circumference (cm) Head Circumference (in) Helmet Size Recommended Models
45-49 17.7-19.3 X-Small Giro Scamp XS, Bell Lil Ripper Toddler
46-50 18.1-19.7 Small Lazer Lil Gekko, Lil Gekko MIPS
47-50 18.5-19.7 Small Nutcase Baby Nutty
47-54 18.5-21.3 Child Bell Sidetrack II MIPS Child
48-51 18.9-20.1 X-Small Bell Sanction Full Face XS
48-52 18.9-20.5 Toddler Nutcase Little Nutty, Bell Lil Ripper Child
49-53 19.3-20.9 Small Giro Scamp S
50-56 19.7-22.0 Medium Lazer Gekko, Gekko MIPS
50-57 19.7-22.4 Medium Giro Tremor MIPS, Bell Sidetrack II MIPS Youth, Giro Hale MIPS
52-54 20.5-21.3 Small Bell Sanction Full Face S
52-56 20.5-22.0 Junior/Small Lazer J1 Junior, Nutcase Adult S, Lazer Adult S
55-57 21.7-22.4 Medium Bell Lil Ripper M, Lazer Adult M, Nutcase Adult M
58-60 22.8-23.6 Large Bell Sanction Full Face L
58-62 22.8-24.4 Large Lazer Adult L
60-64 23.6-25.2 Large Nutcase Adult L

 

How a Kid’s Helmet Should Fit

  1. Position: The helmet should sit level on your child’s head, not tipping forward or backward. The front of the helmet should be two fingers' width above the eyebrows.
  2. Adjustment: Use the retention mechanism (often a ratchet dial) to snugly fit the helmet around the head. The chin strap should be snug but comfortable.
  3. Comfort: Trim or tuck away any excess strap material to prevent irritation.

What to Look For in a Kid’s Helmet

  • Safety Standards: Ensure the helmet meets Snell B90/B95 standards.
  • Visor: Consider a helmet with an integrated visor for sun protection.
  • Padding: Focus on the fit rather than the thickness of internal foam padding.
  • Style: While style is important, prioritize function and fit.

By following these guidelines, you can ensure that your child’s helmet provides the best possible protection while riding their bike.

For more details, you can visit the ReadySetPedal Kids Bike Helmet Size Chart (Ready Set Pedal)​​ (Ready Set Pedal)​.

 

 

 

 

 

 

 

Step 2. Choose your helmet.  The chart below shows which helmets fit for each head size.  

 

45cm

46cm

47cm

48cm

49cm

50cm

51cm

52cm

53cm

54cm

55cm

56cm

57cm

58cm

59cm

60cm

61cm

62cm

63cm

64cm

Giro Scamp Helmets Size X-Small

45-49cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bell Lil Ripper Helmets Size Toddler

45-52cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Lazer Lil Gekko and Lil Gekko MIPS Helmets

46-50cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Nutcase Baby Nutty Helmet

47-50cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bell Sidetrack II MIPS Helmets Size Child

47-54cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bell Sanction Full Face Helmet Size X-Small

48-51cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Nutcase Little Nutty Helmet

48-52cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bell Lil Ripper Helmet Size Child

48-55cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Giro Scamp Helmets Size Small

49-53cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Lazer Gekko and Gekko MIPS Helmets

50-56cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Giro Tremor MIPS Helmets

50-57cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bell Sidetrack II MIPS Helmets Size Youth

50-57cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Giro Hale MIPS Helmets

50-57cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bell Sanction Full Face Helmet Size Small

52-54cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Lazer J1 Junior Helmet

52-56cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Nutcase Adult Small Helmet

52-56cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Lazer Adult Small Helmet

52-56cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bell Sanction Full Face Helmet Size Medium

55-57cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Lazer Adult Medium Helmet

55-60cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Nutcase Adult Medium Helmet

56-60cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bell Sanction Full Face Helmet Size Large

58-60cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Lazer Adult Large Helmet

58-62cm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Nutcase Adult Large Helmet

60-64cm