How we rank products

Every ranking on this site is calculated, not hand-picked. Here is the whole method.

1. Specs come from official ENERGY STAR records

We enter only figures published on an official ENERGY STAR certified-product record and we link the record we used under every product. If a figure isn't published we show "Not listed" instead of guessing.

2. Each spec is scaled from 0 to 1

Each criterion has a fixed reference range, from a "weakest reasonable" value to a "best in class" value (for example 20% to 50% less energy than the U.S. federal standard for standard-width dishwashers, or a Combined Energy Factor of 3.3 to 8.0 for standard dryers). A product's figure is placed on that range and clamped between 0 and 1, so scores stay meaningful as products are added. Yes/no features count as 1 or 0. The ranges are listed below.

3. Weights decide what matters most

Each category lists its criteria and weights on the page. The score is the weighted average, multiplied by 10:

score = 10 × Σ(weight × scaled value) ÷ Σ(weight)

4. How missing data is scored

If a spec isn't published, the product scores at the lowest value any product in that category actually published, so an unpublished figure never outranks a published one. The page marks each such cell with an asterisk. Yes/no features that aren't stated count as no. Nothing is ever scored at the category average.

5. Prices and ratings switch on automatically

When our retailer feeds supply a current price or customer rating for at least 60% of products in a category, two more criteria join the formula: Price / value (20%) and Customer rating (15%, discounted when there are few reviews). Until then we show "Check price" and never estimate a price.

6. What the score can't tell you

Specs don't capture installation cost, how loud a motor is in your kitchen or laundry room, or whether a cabinet will fit the opening. Official ENERGY STAR figures can differ from brochure efficiency claims. When we derive a figure from official numbers, such as annual energy use per cubic foot, we label it computed. Use the score to shortlist, then read the pros, cons, safety notes and sources. When we add hands-on testing notes, we label them clearly.

7. Money never changes the order

We earn affiliate commissions from some retailers. Commission rates are not an input to the formula, and no brand can pay for placement. See our affiliate disclosure.

Criteria by category

Standard Dishwashers

• Percent less energy than U.S. federal standard: 28% · range 20 → 50 %
• Water use: 26% · range 3.2 → 2 gal/cycle
• Place-setting capacity: 24% · range 12 → 16 place settings
• Annual energy use: 22% · range 240 → 200 kWh/year

Clothes Washers

• Integrated Modified Energy Factor (IMEF): 28% · range 2.06 → 3.1
• Certified volume: 24% · range 2.2 → 5.5 cu ft
• Annual energy use: 24% · range 250 → 60 kWh/year
• Integrated Water Factor (IWF): 24% · range 4.3 → 2.7

Clothes Dryers

• Combined Energy Factor (CEF): 36% · range 3.3 → 8
• Certified drum capacity: 32% · range 4 → 8 cu ft
• Estimated annual energy use: 32% · range 687 → 200 kWh/year