Estimate real e-bike range using battery watt-hours, assist level, terrain, speed, temperature, cargo, and your own route data.
An electric bike can often cover dozens of miles of everyday travel on one charge. A larger battery may go farther under low assistance and favorable conditions, while sustained climbing, cold weather, heavy loads, higher speeds, and frequent use of high assistance can reduce the real distance substantially.
There is no single range figure that applies to every e-bike. A maximum-range number on a product page helps compare battery capacity and product positioning, but it should not be treated as the mileage that will appear every day. A useful estimate has to account for the energy in the battery, the route ahead, and how much work the motor must do per mile.
Start With Wh, Not Ah Alone
Two common battery specifications are voltage, measured in V, and capacity, measured in Ah. Multiplying them gives the nominal energy in Wh:
Battery energy in Wh = voltage in V × capacity in Ah
For example:
| Battery label | Nominal energy |
|---|---|
| 36V 10Ah | 360Wh |
| 48V 14Ah | 672Wh |
| 48V 20Ah | 960Wh |
| 48V 30Ah | 1,440Wh |
Ah cannot be compared meaningfully without voltage. A 48V 20Ah battery contains a nominal 960Wh, while a 36V 20Ah battery contains 720Wh. Both are labeled 20Ah, but they do not hold the same total energy.
Usable energy generally does not equal nominal Wh exactly. The battery-management system retains a protective reserve, and battery age, temperature, and current condition also affect available capacity. Even so, Wh remains the more useful starting point when comparing two batteries.
When reviewing a Letrigo electric bike or another product that emphasizes Ah, find the voltage and make this conversion first.
Converting Wh Into Miles Requires Energy Use per Mile
The basic range relationship is:
Estimated range in miles ≈ usable battery Wh ÷ average Wh/mile
The complication is that energy use per mile is not constant. It changes with assistance, speed, grades, load, and weather.
Suppose a nominal 960Wh battery produces these average energy-use records on a real route:
| Route record | Calculated result |
|---|---|
| 15Wh/mile | About 64 miles |
| 20Wh/mile | About 48 miles |
| 30Wh/mile | About 32 miles |
These figures only demonstrate how the same battery can produce very different results under different conditions. They are not universal consumption rates for every e-bike. The most reliable Wh/mile figure comes from the actual model on the routes it regularly travels.
If the display or app reports Wh/mile, recording several similar trips creates a useful baseline. If only battery percentage is available, completed distance and percentage used can still provide a rougher estimate.
Why Can the Same Bike Have Different Range This Week and Next?
Assistance Level and Throttle
Higher assistance asks the motor to do more work and generally raises energy use per mile. With sustained throttle use, the battery carries nearly all of the propulsion load. Lower assistance combined with steady pedaling shifts more of that work to the legs.
That does not mean the lowest assistance level is always correct. Higher assistance can improve control during a loaded start, a climb, or a strong headwind. Range should be estimated using the levels that will actually be used every day, not a deliberately frugal test ride designed only to produce the largest number.
Speed and Wind
Air resistance rises substantially as speed increases. On level ground, moving from an easy pace to a faster cruise can increase energy use more quickly than the speed itself increases.
A route with a tailwind outbound and a headwind home is especially easy to misread. Slow battery use during the first half does not mean the return trip will behave the same way. A round trip needs a reserve for the less favorable direction.
Grades and Frequent Starts
A long climb requires continuous work against gravity. A route with frequent traffic lights repeatedly asks the motor to accelerate the entire bike from a stop. Both require more work than steady cruising on level ground.
A mid-drive motor can use the bike's gears to climb efficiently, but only if the bike is shifted into an appropriate gear. Pulling slowly up a hill in a gear that is too high does not become efficient simply because the motor is mounted at the crank.
Total Weight
The relevant figure is the combined weight of the bike, the person, cargo, and accessories, not just the weight of a backpack. Weight may have less effect than expected while cruising steadily on level ground, but the difference grows quickly on hills and routes with frequent starts.
The batteries and drive systems on electric cargo bikes are generally selected with hauling in mind, but a product-page range still cannot replace a loaded test. Children, groceries, pet supplies, a SideCar, or a trailer all belong in the route estimate.
Temperature, Battery Condition, and Mechanical Resistance
Cold weather temporarily reduces the performance available from a lithium-ion battery, and an aging battery gradually loses usable capacity. Low tire pressure, brake drag, a poorly maintained drivetrain, and higher rolling resistance consume energy that would otherwise move the bike forward.
If range has been consistent and then suddenly drops on the same route, inspect the bike and battery before blaming every change on the weather. Our guide to diagnosing rapid e-bike battery drain is better suited to that abnormal situation.
How Should a Product Page's Maximum Range Be Read?
"Up to" describes an upper limit reached under a favorable set of conditions. It is not a promise for every route.
When comparing products, look for the test conditions:
- Which battery version was used?
- Which assistance level was selected?
- Was the surface flat?
- What was the total test weight?
- What were the average speed and number of stops?
- What were the temperature and wind conditions?
- Was extra cargo carried?
- Was the battery new or already used?
When the page does not provide complete test conditions, use maximum range as a reference for battery capacity and system efficiency, not as the plan for a round trip that must be completed.
If the same model offers different battery options, also confirm which version produced the advertised figure. The standard and upgraded batteries should not share one range assumption.
Build a Personal Range Baseline From Real Routes
After buying the bike, repeated records from routes that will remain part of everyday life are more valuable than another online average.
Use this process:
- Charge the battery to the same starting state.
- Select a commonly used assistance level.
- Complete a route of known distance at a normal pace.
- Record the weather, load, elevation gain, and ending battery level.
- Repeat the test at least three times.
- Plan around the worst result, not the best one.
If 40% of the battery is used over 18 miles, a simple projection is:
18 ÷ 40% = about 45 miles
Battery displays are not always perfectly linear, and the final bar may fall faster. The 45-mile result is therefore an estimate for those conditions, not proof that the bike can continue reliably until the display reaches 0.
If an app records Wh/mile, build separate data sets for no cargo, normal cargo, and heavier loads. After several weeks, those figures will usually be more useful for real-life planning than a single laboratory number.
Put a Reserve Into Every Round-Trip Calculation
Do not plan a trip that cannot be interrupted by matching the advertised range exactly to the round-trip distance.
The required range can be broken into:
Planned round-trip distance + possible detour + margin for unfavorable weather or hills + remaining charge at arrival
For example, consider a planned 30-mile round trip, a possible 4-mile detour, and a desired reserve of about 20%. The right question is not whether a configuration "can go 30 miles." It is whether the bike can reliably cover about 42 to 43 miles under a similar load and on similar roads.
The 20% figure is only a planning example, not a mandatory number for every route. Remote areas, night travel, cold weather, children, or heavy cargo call for a more conservative margin. A city route with reliable charging and pickup options may allow the reserve to be adjusted to the actual conditions.
The purpose of a range reserve is not to arrive home with the same percentage every time. It is to prevent a headwind, an unexpected detour, or an incomplete charge from turning into an unfinished return trip.
How Should Robin's 100-Mile Figure Be Evaluated?
The current product page for the Letrigo Robin electric cargo trike lists a removable 48V 20Ah standard battery and an optional 48V 30Ah upgrade. The stated maximum range of 100 miles corresponds to the larger-capacity configuration under favorable operating conditions.
The nominal energy is about 960Wh for the standard battery and about 1,440Wh for the optional 30Ah battery. The larger option has 50% more nominal capacity, but real range will not increase by exactly the same percentage on every route. The larger battery adds weight, and assistance, speed, grades, and cargo still change energy use.
Robin uses a 500W rated mid-drive motor, 130Nm of peak torque, and a Shimano 8-speed drivetrain, and it supports a maximum total payload of 500 lb. Those specifications help it manage grades and heavier loads, but they also explain why a useful test must include real operating conditions. A lightly assisted, unloaded result cannot be applied directly to a full load, frequent starts, or sustained climbing.
For a fixed urban round trip, whether the standard 20Ah battery is enough should be decided from route data. The larger battery has practical value only when regular trips exceed a comfortable range for the standard capacity and the added cost and weight are acceptable.
When Should Efficiency Be Improved, and When Should a Fault Be Investigated?
If range is below the product-page maximum but remains consistent from one trip to the next, begin with the route, assistance, speed, and load. That is normal variation in use.
To travel farther with the same equipment, see our 10 practical ways to increase e-bike range.
If distance suddenly drops under the same weather, route, and load, or the battery falls rapidly from a certain percentage to 0, tire pressure, brake drag, battery connections, battery age, or another system issue deserves separate investigation.
When adding a second battery or range extender, use a setup the manufacturer has confirmed as compatible. Matching voltage does not guarantee that the connector, controller, and battery-management system will work together.
Frequently Asked Questions
How Far Can a 500W E-bike Go?
500W is the motor's rated power, not the battery's energy capacity. Battery Wh, assistance level, route, and load are all needed; motor wattage alone cannot calculate range.
How Many Miles Can a 48V 20Ah Battery Cover?
Its nominal energy is 960Wh. Actual distance depends on energy use per mile. If a real route averages 20Wh/mile, the mathematical estimate is about 48 miles, but protective reserve and a return-trip margin still have to be deducted.
Does a Larger Battery Always Increase Range Proportionally?
Nominal energy rises with capacity, but real range is also affected by the added weight, system efficiency, and travel conditions. On the same model under the same conditions, range will generally increase substantially, but a perfectly proportional gain should not be promised.
Does Higher Assistance Always Use More Energy?
With other conditions held equal, it generally does because the motor is doing more work. Appropriate high assistance can improve control on hills and with heavy loads; there is no need to force an unsuitable low setting simply to save energy.
Why Does Range Drop in Winter?
Cold temperatures temporarily reduce battery performance and raise internal resistance. Some performance returns when the battery reaches a suitable temperature. If the decline remains substantial in warmer conditions, inspect battery health and mechanical resistance.
Is the Remaining-Range Estimate on the Display Accurate?
It is usually a dynamic estimate based on recent energy use and current charge. The figure changes when assistance, grades, wind, or cargo changes. Treat it as a live reference, not a guaranteed arrival distance.
The Bottom Line
To estimate how far an electric bike can go, first convert battery V and Ah into Wh, then apply the energy use per mile from a real route. Assistance, speed, grades, total weight, temperature, and mechanical condition can all produce different results from the same battery.
A maximum-range figure helps compare models, but everyday planning should use a personal route baseline and retain a margin for detours, headwinds, and the trip home. Reliably completing the routes that matter every day is more useful than reaching one maximum mileage figure under exceptional conditions.
