How we judge and rank

A verdict is only useful if you know what produced it. Here is ours.

Where a verdict comes from

Every verdict here is assembled in the same four steps, and each of them leaves something on the page you can check: we read the specifications, the manuals and the standards that apply to the product, we weigh what long-term owners consistently report about it, and we name the source of every figure we publish.

That last rule is the one that does the work. A number with a source can be argued with; a number without one is decoration. Where a figure exists in a manual and contradicts the marketing, we quote the manual. Where no reliable figure exists at all, the page says so and leaves the field empty rather than filling it with something plausible.

What we weigh

We rank on the specifications that decide the job and the ones that decide how long it keeps doing it. In practice that means five things:

• The number that governs the product. The accuracy figure behind a display resolution, the detector resolution behind an upscaled thermal image, the distance-to-spot ratio behind an infrared reading, the measurement category behind a voltage range. Where a maker publishes a headline figure without the one that qualifies it, we say so rather than repeating it.
• The thing that decides whether it stays in use. A laser bright enough to read in the room you actually work in, a probe thin enough to enter the hole you actually have, a tester that needs no battery of its own. Every category has one detail that decides whether a product is used or left in a drawer, and that is the one we describe.
• What is not in the box. The tripod a line laser assumes you own, the receiver a laser needs outdoors, the thread adapter between a 1/4-inch tool and a 5/8-inch head. This is weighted more heavily here than on most sites, deliberately: it is the whole gap between a working purchase and a disappointing one.
• Consumables and serviceability. What leads, fuses, probes, batteries and chalk cost over a season; whether the fuse the manual specifies is still sold; whether a probe plug will still be supplied in five years. This is why a product that performs slightly worse sometimes outranks one that performs better.
• Availability where you are. Each reference is confirmed market by market, and the page says which markets carry a live offer. An instrument nobody sells where you live is not a recommendation, whatever it measures.

Where the evidence comes from

Three sources, weighted differently and always named. Manufacturer specifications and manuals, cited as such rather than repeated as fact — they are reliable for dimensions and unreliable for durability. Published standards where they exist (a stated measurement category, a marked laser class), always flagged as a figure to verify on the current listing rather than a permanent guarantee. And the weight of long-term owner reports, which is the only practical source for the question that matters most: what is this product like in year three, after the warranty and after the honeymoon?

Where a claim rests on one source rather than three, the page says so. Where we could not source a figure at all, the field is left empty and the gap is stated. We never fill one in by inference.

What the ordering means

We publish no scores. There is no number out of ten on this site, and there never has been — a single figure would have to compare a €1 000 thermal camera with a €9 battery tester, and it cannot. What we publish instead is an order: within a category, the sequence is deliberate, and the reasons for it are in the text.

Within a hub the order runs entry, mid, then top. A buyer arrives with a budget rather than with an ambition, and a page that opens on the dearest instrument answers a question nobody asked.

The biases we designed against

Affiliate sites drift towards expensive products, towards whatever is newest, and towards whatever converts. Our defence is structural rather than a promise: no ranking on this site has ever been reordered because of what a product pays, several pages recommend a €15 consumable instead of a new instrument, and no product has ever been placed in exchange for anything.

The one bias we cannot remove is availability. We cover what is genuinely purchasable across Amazon's US, UK, German, French, Italian and Spanish stores, which means excellent equipment sold only through specialist instrument dealers is under-represented here. Where that matters to the recommendation, the page says so.

Safety figures are reported, never derived

Anything that goes near a live circuit, and anything whose reading decides where a hole gets drilled, is a safety item — and this is the rule that governs every page touching them: every accuracy figure, measurement category, laser class and detection depth on this site is reported from the manufacturer's own documentation, with its source named, and never calculated or inferred by us. Where a figure is not published, the page says it is not published rather than offering a plausible one.

The same applies to standards. Where a maker marks a meter CAT III 600 V, a laser class 2 under EN 60825-1 or an instrument to IEC 61010, we report that the manufacturer states it and link to what they publish. We are not a testing body and we do not assess conformity, so nothing here should be read as a judgement that a product meets a standard — and no instrument on this site is presented as calibrated, or as fit for a legal or evidential measurement.

Where this site stops

Nothing here replaces the manufacturer's instructions. Where a job belongs to a qualified person — working on a live installation, testing insulation on an energised circuit, certifying an installation — the page says so instead of talking you through it, even though a page that stops earns nothing. Pages that touch that boundary say it in the text rather than in a disclaimer at the bottom.