Guides
The tools give you an answer. These are the write-ups behind them — what the number means, where the standard method comes from, and the cases where the obvious approach is quietly wrong. Written for people who'd rather understand the tool than trust it.
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Unix timestamps: what that big number actually means
What the epoch counts and what it ignores — seconds vs milliseconds, time zones, leap seconds, negative timestamps, and the 2038 ceiling.
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JPG, PNG, WebP, HEIC — which format, and when
The decision as you actually face it: photo or graphic, transparency or not, who has to open it — plus the generation-loss trap and why resizing beats format tuning.
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What a TDEE number actually tells you
Where the estimate comes from, how wide its real error bars are, why NEAT dwarfs your gym session, and how to turn the guess into a measurement.
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How random is a random picker, really?
Pseudorandom vs cryptographic sources, modulo bias, the shuffle almost everyone implements wrong, and why a fair draw looks rigged to people.
How we check what we publish, and how corrections are handled, is set out in our methodology.