Backpack Sizes: Complete Capacity Guide
Backpack sizes are measured in liters and dimensions.
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Backpack Size by Capacity
Standard backpack volumes for different uses
| Size | Capacity (Liters) | Dimensions (in) | Best For |
|---|---|---|---|
| Small/Daypack | 10-20 L | 14 x 10 x 6 / 35 x 25 x 15 cm | Kids, light day use |
| Medium/School | 20-30 L | 17 x 12 x 7 / 43 x 30 x 18 cm | School, daily commute |
| Large/Travel | 30-50 L | 19 x 13 x 9 / 48 x 33 x 23 cm | Overnight, weekender |
| Hiking | 50-70 L | 24 x 14 x 12 / 61 x 35 x 30 cm | Multi-day trips |
| Expedition | 70+ L | 28 x 16 x 14 / 71 x 40 x 35 cm | Extended backpacking |
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Laptop Backpack Sizing
Backpack sizes by laptop compatibility
| Laptop Size | Compartment (in) | Backpack Capacity | Fits Laptops |
|---|---|---|---|
| 13 inch | 13.5 x 9.5 / 34 x 24 cm | 15-25 L | Up to 13 inch |
| 15 inch | 15.5 x 11 / 39 x 28 cm | 20-30 L | Up to 15 inch |
| 17 inch | 17.5 x 12 / 44 x 30 cm | 25-35 L | Up to 17 inch |
| 18 inch | 18.5 x 13 / 47 x 33 cm | 30-40 L | Up to 18 inch gaming laptop |
School Backpack Sizing by Age
Age-appropriate backpack sizes
| Age Group | Capacity (Liters) | Torso Fit (in) | Features |
|---|---|---|---|
| Preschool (3-5) | 5-10 L | 10-12 / 25-30 cm | Lightweight, padded straps |
| Elementary (6-10) | 10-20 L | 12-15 / 30-38 cm | Multiple pockets, water bottle |
| Middle School (11-13) | 20-30 L | 15-17 / 38-43 cm | Laptop sleeve, organization |
| High School (14-18) | 25-35 L | 16-18 / 40-45 cm | Full laptop support, durability |
| College/Adult | 30-45 L | 17-19 / 43-48 cm | Professional look, tech storage |
Visual Size Comparison
Size comparison visualization.
Size Calculator
Find the right size for your measurements.