CFM vs MPH: what leaf blower specs actually mean

Think of a garden hose. Thumb over the end gives you a fast, narrow jet — high speed, low volume — perfect for blasting a stain off a slab. Thumb off gives you a wide gentle flow — high volume, low speed — perfect for rinsing the whole slab down. A blower nozzle does exactly the same thing to air.

• Wet leaves stuck to concrete: speed. Concentrator nozzle, higher trigger.
• A wide dry driveway: volume. Wide nozzle, moderate trigger, long sweeps.
• Grit in paving joints: speed, held low and close along the joint.
• Grass clippings on a lawn: volume, so they lift and travel rather than tumble.
• Car panels and electronics: neither maxed — use the lowest setting that works.

Battery voltage tells you how much energy is available, not how well the tool converts it. A brushless motor turning at 55,000 RPM behind a well-shaped impeller will out-clear a higher-voltage tool with a cheap brushed motor, because far less of the energy becomes heat and noise instead of airflow.

What is CFM on a leaf blower?

Cubic feet per minute — how much air the tool moves. High CFM sweeps a wide area of dry debris quickly.

What is MPH on a leaf blower?

Miles per hour — how fast the air leaves the nozzle. High MPH breaks debris loose from a surface: wet leaves, grit in joints, matted clippings.

Which matters more, CFM or MPH?

Neither, alone. You need speed to unstick debris and volume to carry it away. A blower with a huge MPH figure through a pinhole nozzle moves almost nothing.

Why do manufacturers quote them separately?

Because they are usually measured under different conditions — often the highest MPH with the narrowest nozzle and the highest CFM with none fitted. Treat quoted figures across different brands as indicative, not comparable.