Methodology
Every number on this site is either sourced (a certified spec pulled from a public registry, cited to it) or computed (a figure we derive with a formula published here). We never blur the two, and we never invent a spec — a missing value renders as "not published," not estimated.
How we source performance specs
Efficiency ratings (IMEF/IWF for washers, CEF for dryers, kWh/yr for dishwashers and refrigerators) and capacity figures come from two public sources, joined on the certified model number:
- DOE CCMS (Compliance Certification Management System,
regulations.doe.gov/certification-data) — the federal certification database covering the full market of certified basic models, including SKU expansion for individual models covered by a basic model. - ENERGY STAR certification data (
data.energystar.gov) — supplies the ENERGY STAR and Most Efficient designations, UPC, and certification/availability dates, and carries the model number that lets us join the two.
Where a registry doesn't disclose a field, that field renders as "not published." We don't interpolate.
The capacity-truth wedge: advertised vs. DOE-adjusted volume
A refrigerator's advertised capacity (the number on the yellow tag and the retail listing) is measured differently than the DOE-adjusted volume used to compute its certified efficiency rating — and the two are documented to diverge by roughly 30–32%. We publish both numbers on every refrigerator/freezer page and never conflate them.
How we compute annual running cost
Our headline metric per product is the estimated annual dollar cost to run it, computed from the certified annual kWh figure and an electricity price:
The default electricity price is the EIA U.S.-average residential rate (currently ~$0.1883/kWh, April 2026), refreshed on the same cadence as the corpus. Every product page with a computed cost also shows the same figure at the cheapest and most expensive state electricity price on record (computed.state_low / computed.state_high), so the national number isn't presented as universal.
For dryers specifically: gas-dryer kWh figures published by the certification registries cover the motor only, never the gas heating BTUs. We never present a gas dryer's electric kWh as its total running cost — gas dryer pages show an honest explanation instead of a dollar figure, and no gas-dryer record in our corpus carries a non-null annual_cost_usd (enforced by our merge pipeline, which fails the build if one shows up).
The thin-content publish floor
Not every certified record gets its own standalone page. A model publishes as a full page only if it has a complete energy block (kWh/yr) and a computed cost (or is a gas dryer with the honest null-cost explanation), plus at least one of: a capacity/volume figure, fit specs, or ENERGY STAR badge data beyond the raw kWh number. Records that don't clear that floor stay in the filterable product database and the plain browse index — findable and comparable, just without a thin, mostly-empty page of their own. Right now that's 2,094 of 15,477 records (mostly washers and dryers missing a published kWh/cost figure).
What we don't do
- No star ratings. We don't run a proprietary score that collapses efficiency, capacity, and price into one undisclosed number. We show the sourced numbers and let you sort by what matters to you.
- No pay-for-placement. Rankings are strictly by a stated, verifiable metric, computed identically for every unit.
- No invented specs. If a registry doesn't publish a value, we mark it "not published" rather than estimate it.
Freshness
The corpus was pulled and gate-verified from DOE CCMS and ENERGY STAR on 2026-07-18. Our automated per-page freshness-stamp pipeline (which will show the exact pull date on every page) isn't wired yet — until it is, this reads: date pending first freshness stamp. Re-pulls will follow the same DOE CCMS / ENERGY STAR cadence documented in this repo's ARCHITECTURE.md.
Affiliate disclosure
See the full affiliate disclosure. No retailer affiliate program is live yet; buy links either point to an untagged retailer search or say so plainly. Any future affiliate relationship will never influence which appliance appears or how it's ranked.
Corrections
Found a wrong spec, a stale figure, or a mismatched model number? Email erinrose451@gmail.com with the model number and what's wrong. We fix verified errors and update the "last updated" date on the affected page.
Download the data
The full derived dataset — every certified product, its sourced specs and (once wired) our computed running cost — is published machine-readable and licensed CC-BY-4.0: download /dataset.json. No affiliate parameters, no sign-up.