Every outboard. Every prop brand.
Find the pitch that puts your motor in its full-throttle window, then compare props across brands, not one maker's catalogue. Free.
Land full throttle inside the window. Everything else follows.
Outboard makers publish a full-throttle rpm window for every motor. As a rule of thumb, one inch of pitch moves full-throttle rpm by roughly 150–200 rpm; Propbench works it out from your motor, gearcase ratio and boat.
The motor can't reach its window. Slow hole-shot, lugging, extra load on the powerhead.
- Drop pitch
- Check trim and engine height first
Full throttle lands in the maker's window with a normal load. Best balance of speed, fuel and engine life.
- Keep the pitch
- Fine-tune with cup or blade count
The motor revs past the window or hits the limiter. Wasted top speed, more wear.
- Add pitch
- Rule out ventilation and blowout
Five props that fit. Not one.
One answer per brand, ranked by how close each lands to the middle of your window. Paid listings never change the ranking.
| Brand | Series | Material | Blades | D × P, in | Est. WOT | Why |
|---|---|---|---|---|---|---|
| Mercury | Black Max | Aluminium | 3 | 14.5 × 19 | ≈ 5,480 | Budget, protects the gearcase |
| Mercury | Enertia | Stainless | 3 | 14.6 × 19 | ≈ 5,450 | Stiffer, better at speed |
| Solas | Amita 3 | Aluminium | 3 | 14.5 × 19 | ≈ 5,470 | Cross-brand alternative |
| PowerTech | OFS | Stainless | 4 | 14.25 × 19 | ≈ 5,360 | Grip and lift, heavy loads |
| Michigan Wheel | Vortex | Aluminium | 3 | 14.5 × 19 | ≈ 5,480 | Spare or backup prop |
Aluminium or stainless?
Both can be right. The selector shows both where they fit, with the trade-offs.
| Feature | Aluminium | Stainless |
|---|---|---|
| Price | Lower | Higher |
| Blade stiffness | Flexes under load | Holds pitch at speed |
| Blade thickness | Thicker | Thinner, more efficient |
| In a strike | Gives way, often protects the gearcase | Transfers more of the impact |
| Repair | Cheaper, quicker | Possible, costs more |
| Best for | Most boats, spares, shallow water | Faster boats, heavy loads, offshore |
Multi-engine rigs, counter-rotation included.
Port counter-rotating
Propbench pairs a standard and a counter-rotating prop of the same model, so the boat tracks straight.
Centre motor standard
Centre engine standard rotation, outers paired. Load shared across three props changes the pitch.
Auxiliary motors
Small kickers and tenders, from 2.5 hp, with their own window and prop.