Every commercial microwave gets a score from 0 to 100% built from five 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. Microwaves are grouped by output power, under 1,200 W and 1,200 W and up, and use the same scale in both groups.
| Factor | Measures | Weight |
|---|---|---|
| Power | rated cooking (output) power | 25% |
| Capacity | cavity capacity in cubic feet | 15% |
| Programmability | stored programs, cooking stages and power levels | 25% |
| Duty rating | the maker's light, medium or heavy duty rating | 15% |
| Warranty | parts and labor warranty, plus magnetron coverage | 20% |
Where the numbers come from
Power, capacity, programming, electrical needs, dimensions and warranty come from the maker’s spec sheet and warranty certificate, or from the maker’s own copy on a retail listing where no spec sheet is published. Prices are checked at the stores each page links to, and the lowest price is used.
The factors
Power is the rated cooking (output) power: 900 W scores zero and 2,200 W full marks. Input power and current draw are listed but not scored.
Capacity is the cavity size: 0.5 cu ft scores zero and 1.2 cu ft full marks.
Programmability is 60% stored programs, 20% cooking stages and 20% power levels. Programs are scored on a log scale, so going from 10 to 100 counts the same as going from 1 to 10: one program or a dial scores zero and 100 programs full marks. One stage scores zero and 4 full marks, and one power level scores zero and 11 full marks. A model with one-touch memory pads but no published program count is scored on its pads. When only some of the three are published, the factor uses those and is marked estimated.
Duty rating is the maker’s own rating: light duty scores zero, medium duty half and heavy duty full marks. Amana’s Low, Medium and Heavy Volume ratings count as light, medium and heavy duty.
Warranty is 70% parts and labor coverage and 30% magnetron coverage, each scored from 1 year (zero) to 3 years (full marks). When a maker doesn’t state separate magnetron coverage, the parts and labor term is used for both.
What isn’t scored
Input power, current draw, voltage and plug, inside and outside dimensions, weight, door handle, energy feed, number of magnetrons, stacking, USB menu loading, Braille keypads, certifications and release date 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. The exception is warranty: a maker that doesn’t publish one gets no warranty counted, so that factor scores zero, the same as a one-year warranty, and is marked 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.