Methodology
How the BPR score is built
Every ranking on this site follows the same procedure, whether the subject is a washing machine, a tyre or a sunscreen. This document sets it out in full.
The BPR score is the mean of four component scores on a 0–10 scale. No multipliers, no weightings hidden from the reader, no discretionary points.
Step 1
The key parameter
For every category we name the one measure that genuinely decides usefulness and that can be verified in documentation or in studies: the concentration of an active ingredient in a cosmetic, the wash performance class of a washing machine, the guaranteed throughput of a broadband plan.
The key parameter appears on the ranking page together with the source of its value. It is what separates an analysis from a collection of opinions — it puts every product on one declared axis.
Step 2
Four component scores
Each product receives four scores on a 0–10 scale:
- Composition and specification — declared composition and specification: active ingredients and their concentrations, classes, standards, technical parameters, and what the manufacturer leaves unsaid.
- Evidence and studies — verification of claims in outside sources: laboratory reports, industry testing, safety data sheets, certificates and regulatory decisions.
- Owner feedback — analysis of verified reviews written after extended use, together with recurring fault reports for the model or series.
- Cost and value — price set against what the product delivers, plus costs incurred later: consumables, energy, servicing, subscriptions. The horizon matches the category — years of running costs for an espresso machine, price and durability alone for a pair of shoelaces.
A score that cannot be traced to a source is not awarded. In that case the product does not enter the ranking.
Step 3
Score and verbal grade
The BPR score is the arithmetic mean of the four component scores, rounded to one decimal place. Each component carries equal weight.
Verbal grade thresholds
- 9.0–10 — excellent, the benchmark in its category
- 8.0–8.9 — good, minor trade-offs
- 7.0–7.9 — fair, behind the leaders
- 6.0–6.9 — acceptable, a clear weakness in one area
- below 6.0 — poor, not published in the ranking
Differences smaller than 0.3 points fall inside the significance threshold. Products in that band are treated as equivalent, and the choice comes down to price, warranty or service availability.
Step 4
Sources and their hierarchy
Not every source carries the same weight. The order in which we resolve contradictions:
- 1. Results from accredited laboratories and consumer organisations.
- 2. Official documents: declarations of conformity, regulatory decisions, register entries, safety data sheets.
- 3. Manufacturer documentation: specification, composition, manual, warranty terms.
- 4. Verified owner reviews written after extended use.
Where manufacturer documentation contradicts an outside study, the study governs the score and the discrepancy is described in the text of the ranking.
Cost
Why the horizon is not fixed
Cost is calculated as the nature of the product dictates. For a washing machine, an espresso machine or a subscription service a multi-year calculation makes sense — energy, consumables and servicing can exceed the purchase price. For products bought and used without further spending, what matters is price against build quality and durability.
Every ranking states exactly what entered this score and over what horizon.
Scope
What the score does not tell you
Scores are comparable only within a single category. An 8.6 for a washing machine and an 8.6 for a face cream do not mean the same thing, because each category is analysed on a different set of parameters.
The score also excludes taste, design and availability in a particular shop. It measures usefulness as the data describes it, not suitability for every buyer.
Updates
How often rankings are refreshed
Prices are checked weekly, the composition of a ranking monthly, and a full re-analysis runs every twelve months — or sooner if a manufacturer changes the formulation, the specification or the warranty terms.
The address of a ranking never changes when it is updated, and the date of the last change is always visible above the results table.
Questions and answers
Frequently asked questions
Can a score be bought?+
No. We accept no payment for a place in a ranking or for a score, publish no sponsored content, and show no brand its result before publication.
Do you publish your sources?+
Yes. Every ranking lists the documents, studies and registers the scores rest on, and every product shows the value of the key parameter together with where it came from.
What happens when a manufacturer changes a product?+
We treat it as a new product: the score is recalculated and the ranking records the date and scope of the change. Old scores do not carry over to a new formulation.
Rankings
Latest analyses
Everything described here is applied in practice in the rankings below.
