Every booster pump gets a score from 0 to 100% built from six factors, which maps onto the 5-point rating shown on the site (a 0% score would be 1.5 stars; a perfect score, 5). Each factor is scored against fixed reference points, not against the other products in the list, so adding a new model never moves another model’s rating. Pumps are grouped by drive, variable speed and fixed speed, on the same scales.
| Factor | Measures | Weight |
|---|---|---|
| Value | price per gallon a minute of maximum flow | 30% |
| Flow | maximum flow | 15% |
| Pressure | maximum head the pump adds | 15% |
| Protection | stops itself on running dry or overheating | 10% |
| Noise | rated sound level | 10% |
| Warranty | warranty length | 20% |
Where the numbers come from
Flow, head, motor size, protection, noise and warranty come from the maker’s spec sheet, pump curve, manual or product page. Prices are checked at Amazon, the maker’s own store and home improvement retailers, and the lowest is used.
The factors
Value is the current price divided by the maximum flow, on a log scale, so halving the price per gpm always counts the same. $60 per gpm scores zero and $8 full marks.
Flow is the maker’s maximum flow: 8 gpm scores zero and 30 gpm full marks. When a maker publishes only a rated flow, that stands in for the maximum in value and flow, and both factors are marked estimated.
Pressure is the maximum head the pump adds: 60 ft (about 26 psi) scores zero and 180 ft (about 78 psi) full marks. Where a maker gives only pressure, it’s converted at 2.31 ft per psi.
Protection is 60% for dry-run protection, which stops the pump when no water is coming in, and 40% for overheat protection on the motor.
Noise is the maker’s sound level: 70 dBA scores zero and 45 dBA full marks.
Warranty is the maker’s warranty: 1 year scores zero and 3 years full marks.
What isn’t scored
Motor size, input power, the highest inlet pressure, a built-in tank, outdoor rating, port size and weight are listed but not scored.
Missing data
If a figure isn’t published, that factor gets the neutral middle score (50) and the product page marks it as estimated.
Ties and discontinued models
Products are ranked by score within each group. Discontinued models stay listed but rank below every current model and can be hidden with the “Hide discontinued” filter.