How long does it take to mow a lawn?

Active push-mowing of a 100 m² lawn takes roughly 5-10 minutes, and a 500 m² lawn about 25-35 minutes (the calculator applies the industry-standard 80% efficiency factor for turning and overlap). Add 10-20 minutes for edging, raking and emptying the box on a real cut. Self-propelled mowers are about 20% faster, and ride-on mowers cut large lawns 3-4 times faster than walking.

What mower width should I choose?

For small lawns (under 100 m²), a 30-35 cm cut width is fine. Medium lawns (100-300 m²) suit 35-45 cm. Large lawns (300+ m²) benefit from 45-55 cm. Ride-on mowers typically have 76-107 cm cutting decks.

How much overlap should I leave between passes?

A 10% overlap is standard and prevents missed strips. On uneven ground or with irregular edges, increase to 15-20%. Professional groundskeepers often use 10-15% overlap for a clean finish.

Do obstacles really add that much time?

Yes, each obstacle (tree, flower bed, ornament) adds 1-2 minutes for manoeuvring around it. A lawn with 10 obstacles could add 15-20 minutes to your total mowing time compared to an open lawn.

How often should I mow my lawn?

Weekly mowing is ideal from March to October in the UK. In peak summer, twice weekly may be needed. In spring and autumn, fortnightly is usually sufficient. Never cut more than one-third of the grass blade height at once.

GardenCalcs

Lawn Mowing Time Calculator — How Long to Mow Your Lawn

Estimate mowing time based on lawn size, shape, mowing method, and obstacles.

Lawn Area

Total grass area to mow in square metres (length × width); subtract beds and paths

Lawn ShapeRectangle = open, fewest turns; L-shape and irregular add 20-35% for extra turns and edge-work

Mowing MethodPush and self-propelled are attended walk-behind; ride-on suits 300+ m²; robot runs unattended

Obstacles

Trees, beds, ornaments etc.

Mowing FrequencyDrives the weekly time figure; UK lawns often need twice-weekly cuts in peak summer

How We Calculate This

The calculator estimates mowing time using:

Effective cut width: Mower width minus overlap
Walking/driving speed: Push ~4 km/h, self-propelled ~4.8 km/h, ride-on ~8 km/h
80% efficiency factor: Real mowing loses ~20% of time to turns, start-stop and overlap beyond the strip (industry standard — acres/hr = mph × deck ÷ 124 at 80%)
Shape factor: Rectangles are fastest; irregular shapes add 20-35% time
Obstacle time: ~1.5 minutes per obstacle for manoeuvring
Weekly commitment: Single-mow time × mows per week (peak summer often twice weekly)

Robot mowers run autonomously over several hours rather than in attended minutes, so their per-cut workload is shown as unattended run-hours.

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates based on standard gardening guidelines. Results may vary with soil conditions, climate, and plant varieties.