E-Bike Range Calculator: How Far Will You Actually Go?

Stop guessing your e-bike's range. This guide gives you the exact formula, real-world Wh/mile data, and a calculator for your specific build.

E-bike range claims from manufacturers are almost always wildly optimistic. A '50-mile range' battery might give you 30 miles in real-world riding, or 15 miles if you're heavy, riding in hills, in cold weather, on throttle-only. This guide gives you the tools to calculate actual range for your specific build.

By the end of this page, you'll be able to predict your e-bike's range to within 10% accuracy, regardless of motor type, battery capacity, terrain, or rider weight.

The Range Formula

Range = Battery Wh ÷ Wh per mile consumption

The formula is simple. The complexity is in accurately estimating Wh per mile for your specific situation. That's what this guide helps you calculate.

Battery Wh is easy: just multiply volts by amp-hours. A 48V 15Ah battery is 720Wh. A 52V 20Ah battery is 1,040Wh. The number is on your battery spec sheet.

Wh per mile is harder. It depends on motor wattage, rider weight, terrain, assist level, weather, tire pressure, and dozens of other factors. The next section gives you baseline numbers; later sections help you adjust for your specific situation.

Baseline Wh per Mile by Motor Type

These are real-world averages from our testing and from aggregated data from e-bike forums. Your mileage will vary based on the adjustments in the next section.

250W motor (pedal assist level 2): 10-12 Wh/mi
250W motor (full assist): 15-18 Wh/mi
500W motor (pedal assist level 2): 12-15 Wh/mi
500W motor (full assist): 18-25 Wh/mi
500W motor (throttle only): 25-30 Wh/mi
750W motor (pedal assist level 3): 18-25 Wh/mi
750W motor (full assist): 25-35 Wh/mi
750W motor (throttle only): 30-40 Wh/mi
1000W motor (pedal assist level 3): 25-30 Wh/mi
1000W motor (full assist): 30-40 Wh/mi
1000W motor (throttle only): 35-50 Wh/mi
1500W motor (throttle only): 45-60 Wh/mi

Examples:
- 500W hub kit + 48V 15Ah (720Wh) battery, level 2 assist: 720 ÷ 13.5 = 53 miles
- 750W BBS02 + 48V 15Ah (720Wh) battery, full assist: 720 ÷ 30 = 24 miles
- 1000W BBSHD + 52V 20Ah (1040Wh) battery, throttle only: 1040 ÷ 42 = 25 miles

Adjustments: Rider Weight

The baseline numbers assume a 175-pound rider. Adjust for your weight:

150 lb rider: subtract 10% from Wh/mi
175 lb rider: baseline (no adjustment)
200 lb rider: add 10% to Wh/mi
225 lb rider: add 20% to Wh/mi
250 lb rider: add 30% to Wh/mi
275 lb rider: add 40% to Wh/mi
300+ lb rider: add 50% to Wh/mi

Example: A 250-pound rider on a 750W BBS02 with 48V 15Ah battery, full assist: 30 Wh/mi × 1.30 = 39 Wh/mi. Range = 720 ÷ 39 = 18.5 miles (vs 24 miles for a 175-pound rider).

Adjustments: Terrain

Hills have an enormous impact on range. Use these adjustments:

Flat terrain (under 3% average grade): baseline (no adjustment)
Rolling terrain (3-5% average grades): add 20% to Wh/mi
Hilly terrain (5-10% average grades): add 50% to Wh/mi
Very hilly (10%+ average grades): add 100% to Wh/mi (double consumption)
Mountainous (sustained 15%+ climbs): add 150% to Wh/mi

Note: hills consume more energy going up than they recover going down. Regenerative braking (only on direct-drive hub motors with compatible controllers) recovers maybe 5-10% of descent energy, not enough to materially affect range.

Example: A 750W BBS02 with 48V 15Ah battery in hilly terrain (50% adjustment): 30 Wh/mi × 1.50 = 45 Wh/mi. Range = 720 ÷ 45 = 16 miles.

Adjustments: Weather

Weather affects range significantly, especially temperature.

Ideal temperature (60-75°F): baseline
Cold weather (32-50°F): add 15% to Wh/mi (battery less efficient, lubricants stiffer)
Very cold (under 32°F): add 30% to Wh/mi
Hot weather (85-95°F): add 5% to Wh/mi (motor cooling less effective)
Very hot (over 95°F): add 15% to Wh/mi (thermal cutoff may limit power)

Headwind (10 mph): add 15% to Wh/mi
Strong headwind (20 mph): add 35% to Wh/mi
Tailwind: subtract 10-15% from Wh/mi

Example: 750W BBS02 + 48V 15Ah battery in cold weather with 10 mph headwind: 30 × 1.15 × 1.15 = 39.7 Wh/mi. Range = 720 ÷ 39.7 = 18.1 miles.

Adjustments: Assist Level and Throttle

Your assist level has the single biggest impact on range — bigger than any other variable.

Level 1 (eco, 30% assist): subtract 40% from baseline Wh/mi
Level 2 (touring, 60% assist): baseline
Level 3 (sport, 100% assist): add 30% to baseline Wh/mi
Level 4 (turbo, 150% assist): add 70% to baseline Wh/mi
Throttle only (no pedaling): add 100-150% to baseline Wh/mi

Example: 750W BBS02 + 48V 15Ah battery, level 1 eco mode in flat terrain: 30 × 0.6 = 18 Wh/mi. Range = 720 ÷ 18 = 40 miles. Same setup at full throttle: 30 × 2.0 = 60 Wh/mi. Range = 720 ÷ 60 = 12 miles.

The difference between eco mode (40 miles) and throttle-only (12 miles) is more than 3x — your assist level matters more than your battery size.

Adjustments: Bike Weight and Tire Pressure

Heavier bikes and under-inflated tires both reduce range.

Bike + motor weight:
- Under 40 lb total: subtract 5% from baseline
- 40-55 lb total: baseline
- 55-70 lb total: add 8% to baseline
- 70+ lb total (cargo, fat bikes): add 15% to baseline

Tire pressure:
- At maximum sidewall pressure: baseline
- 10 psi under max: add 5% to baseline
- 20 psi under max: add 15% to baseline
- 30+ psi under max: add 30% to baseline

Tire width:
- 28mm road tires: subtract 10% from baseline
- 40mm hybrid tires: baseline
- 2.0" mountain tires: add 8% to baseline
- 4.0" fat tires: add 25% to baseline

Knobby tread pattern: add 8-12% to baseline

Putting It All Together: Real Example

Let's calculate range for a real-world build:

Build: 750W BAFANG BBS02 + 48V 15Ah (720Wh) battery on a 50lb hybrid bike, 200lb rider, level 3 assist, hilly terrain, 60°F, properly inflated 40mm tires.

Baseline (750W, level 3 assist): 30 Wh/mi
Rider weight adjustment (200lb): × 1.10 = 33 Wh/mi
Terrain adjustment (hilly): × 1.50 = 49.5 Wh/mi
Weather adjustment (60°F): × 1.00 = 49.5 Wh/mi
Bike weight adjustment (50lb): × 1.00 = 49.5 Wh/mi
Tire adjustment (40mm, proper pressure): × 1.00 = 49.5 Wh/mi

Final consumption: 49.5 Wh/mi
Range: 720 ÷ 49.5 = 14.5 miles

That's a meaningful drop from the 'ideal conditions' estimate of 24 miles. This is why manufacturer range claims are so misleading — they're calculated for ideal conditions that almost never exist in real-world riding.

For comparison, here's the same build on flat terrain in eco mode (level 1):
Baseline: 18 Wh/mi (level 1 assist)
Rider weight: × 1.10 = 19.8 Wh/mi
Terrain (flat): × 1.00 = 19.8 Wh/mi
Range: 720 ÷ 19.8 = 36.4 miles

The same build gives 14.5 miles in hilly full-assist conditions or 36.4 miles in flat eco-mode conditions — a 2.5x range difference based purely on how you ride.

Battery Sizing Recommendations

Based on our range calculations, here are our battery capacity recommendations by use case:

Casual rider (5-10 mile rides, flat terrain): 48V 10-13Ah (480-624Wh). Minimum viable capacity.

Daily commuter (10-20 mile round trip, mixed terrain): 48V 13-15Ah (624-720Wh). Sweet spot for most riders.

Long-distance commuter (20-40 mile round trip): 48V 17-20Ah (816-960Wh). Enough range for any commute with headroom.

Cargo bike (hauling kids/gear): 48V 20Ah+ (960Wh+). Cargo adds 50-100% to Wh/mi consumption.

Touring/long-distance rider: 48V 20-30Ah (960-1440Wh), or carry a second battery.

Off-road/trail rider: 48V 15-20Ah (720-960Wh). Off-road consumes 25-50% more Wh/mi than paved.

High-power build (1000W+ motor): 48V 20Ah+ (960Wh+). Big motors are thirsty — bigger battery needed for reasonable range.

When in doubt, buy more battery. The cost premium for 15Ah vs 13Ah is typically $40-60, and the range headroom is worth it. A battery that's barely adequate in summer will be inadequate by winter as capacity drops 20-30%.