The Coffee Handbook exists so you can buy a grinder or a machine once instead of three times. That only works if you can see how we arrived at a recommendation, so here is the whole method.
Where our numbers come from
Burr diameters, pump pressure, boiler capacity, dose retention and brew ratios come from manufacturer specification sheets first, and from published teardowns and independent measurement wherever those exist to check them against. When a manufacturer figure and a measured figure disagree, we print both and say which one we trust.
Some numbers in coffee are marketing rather than measurement. “15 bar” is the most common: it describes what a pump can produce dead-headed, not what reaches the coffee, which is closer to 9 bar on a well-built machine. Where a spec is routinely quoted in a misleading way, we explain what it actually means rather than repeating it.
Retention figures are the other soft number. A grinder’s retention depends on burr geometry, dose size and how it is operated, so a single figure is only meaningful with the conditions attached. We give the conditions.
How we choose what to feature
We start from the question a buyer is actually asking — “what should I grind with under $500”, not “what is new this month”. Gear is included because it answers a common buying question, and equipment with no affiliate programme is covered on exactly the same terms as equipment that pays.
We are willing to recommend nothing. If a category is currently a poor buy, or the sensible advice is to keep what you have and upgrade the grinder instead, that is what the guide says.
Older equipment stays in guides for as long as it is the right answer. The Rancilio Silvia and the Baratza Encore have both been in production for years, and neither is worse this year than it was last year. Recency is not a ranking factor.
How we make money
Some links here are affiliate links: if you buy through them, the retailer pays us a commission at no extra cost to you. That is the entire business model — there are no sponsored placements, no paid reviews, and no brand has ever paid to appear or to rank higher.
Commission rates differ between retailers and between products. They are not consulted when we decide what to recommend or how to order a list, and the person writing a guide does not know what any given link pays. Any article containing affiliate links carries a disclosure at the top of the page.
Corrections
Coffee equipment changes: burrs get revised, models get quietly discontinued, and prices move. When we find something out of date we fix it and note what changed.
If something here is wrong, tell us. Corrections to a factual error are made promptly, and material changes are dated so you can see what was altered and when.