Robot Runtime Calculator

Know how long your garden robot should run. Compare speeds, widths, and real‑world efficiency today. See charges needed, recharge breaks, and total finish time.

Calculator inputs
Enter your garden and robot settings
Result appears above after you submit.
Total mowable surface area.
1.00 simple, 1.10–1.30 complex edges.
Extra passes due to path overlap.
Stops, turning, and tight navigation.
Choose how coverage is calculated.
Real-world cutting efficiency.
Average moving speed while cutting.
Deck width or effective swath.
Use a manufacturer or measured rate.

Watt-hours on the battery label.
Typical draw while mowing.
Minutes between sessions.
0 means no session limit.
Spread mowing across these days.
100% equals one full pass weekly.
Reset

Formula used

The calculator first expands your garden area into an effective area: Effective Area = Area × Shape Factor.

If you choose the derived method, it computes effective coverage: Coverage = (Speed × 1000) × (Width ÷ 100) × Efficiency × (1−Overlap) × (1−Obstacle), producing m²/hour.

Runtime for a full pass is: Hours = Effective Area ÷ Coverage. Battery runtime per charge is: Minutes/Charge = (Battery Wh ÷ Power W) × 60.

Sessions are calculated by dividing required minutes by the session cap (battery limit, or your max session if set). Elapsed time adds recharge breaks.

How to use this calculator

  1. Enter your garden area and choose a realistic shape factor.
  2. Select a coverage mode: derived settings or direct m² per hour.
  3. Set overlap and obstacle time to reflect real navigation.
  4. Add battery Wh, average power, and recharge minutes.
  5. Choose days per week and your weekly coverage target.
  6. Press Calculate runtime to see results above the form.

Example data table

Scenario Area (m²) Coverage (m²/h) Battery (Wh) Power (W) Runtime/Charge (min) Full Pass (hours)
Small lawn, simple edges 200 180 120 28 257 1.22
Medium lawn, obstacles 500 240 150 30 300 2.29
Large lawn, complex edges 1200 300 300 45 400 4.40
Example values are illustrative. Measure your robot for best accuracy.

Coverage rate inputs and why they matter

Runtime begins with coverage capacity in square meters per hour. The derived method uses travel speed and cutting width to form a theoretical area rate, then applies field modifiers. This mirrors how garden robots move in arcs, pause to re-orient, and slow near borders. Compare settings by the resulting m²/h because it drives later outputs overall such as sessions and finish time.

Efficiency, overlap, and obstacle adjustments

Efficiency represents how much of the theoretical swath becomes finished mowing after turning losses, sensor checks, and boundary behavior. Overlap reduces net progress when the robot re-traces paths to avoid missed strips or to correct random patterns. Obstacle time accounts for stops, tight maneuvers around beds, and slow navigation on slopes. If your lawn has many islands or narrow passages, raise obstacle time first, then refine overlap after observing coverage quality.

Battery capacity and average power draw

Battery watt‑hours describe stored energy, while average watts describe consumption rate. Minutes per charge are estimated by dividing watt‑hours by watts and converting to minutes. Power draw is not constant: taller or wet grass loads the blade motor, slopes increase traction demand, and frequent turning can spike current. If you monitor charger logs or smart plugs, update the average watts to match your garden’s typical conditions for a tighter runtime estimate.

Sessions, caps, and recharge-driven elapsed time

A single “runtime” number can hide operational constraints. Many gardens require quiet hours, irrigation breaks, or short runs for security and supervision. Setting a max session caps each run and can increase total sessions. The calculator estimates elapsed time by adding recharge breaks between sessions, so you can plan completion windows on the clock.

Weekly planning and workload distribution

Weekly coverage target scales the full-pass requirement to match growth rate and desired appearance. 100% equals one complete pass each week; higher values suit fast spring growth or fine turf where clippings should stay short. Spreading runtime across selected days smooths workload, keeps clipping return consistent, and reduces long continuous operation that can warm batteries. Use the daily plan as a baseline, then adjust seasonally after rainfall, fertilization, and shade changes.

FAQs

1) Should I use derived coverage or direct coverage rate?

Use derived coverage when you know speed and width. Use direct coverage when you have a measured or manufacturer m²/hour figure and want to bypass efficiency tuning.

2) What shape factor should I choose for my garden?

Start with 1.00 for simple rectangles. Use 1.10–1.20 for curved borders and beds. Go up to 1.30 when tight corridors or many edges force extra turning.

3) Why does overlap reduce coverage so much?

Overlap represents repeated passes. Even small overlap values can add up across the whole lawn, especially when the robot corrects paths near borders or navigates around obstacles.

4) How accurate is battery runtime per charge?

It is an estimate based on average watts. Actual runtime varies with grass height, slope, wheel slip, and blade load. Update power draw after observing a few real sessions.

5) What does “elapsed time” include?

Elapsed time includes mowing minutes plus recharge breaks between sessions. It helps you plan completion windows, especially when multiple sessions are required for a full pass.

6) How do I set a sensible weekly coverage target?

Use 100% for one full pass weekly. Increase to 120–160% during fast growth seasons, and reduce below 100% in slow growth periods to save energy and wear.

Quick tips
  • Use 1.10–1.25 shape factor for curved borders.
  • Increase overlap if stripes or missed edges appear.
  • Obstacle time rises with trees, beds, and slopes.
  • Power draw changes with grass height and moisture.
  • Set a max session to avoid late-night operation.
Download options

CSV and PDF downloads appear after calculation.

Downloads use the last computed values in this browser session.

Related Calculators

Pool Surface Area CalculatorPool Waterline Length CalculatorPump Flow Rate CalculatorFilter Backwash CalculatorCartridge Filter Area CalculatorHeater Size CalculatorSolar Heater Sizing CalculatorPool Cover Savings CalculatorAuto Fill Time CalculatorDrain Time Calculator

Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.