About
XP Calcs is an independent collection of planning tools for players of Old School RuneScape. Its purpose is narrow: turn public game mechanics into calculations that can be inspected, copied and checked.
Who runs the site and what it is not
The site is built and maintained by one small independent team as a fan project. It is not affiliated with, endorsed by or sponsored by the game publisher, and it never presents itself as an official source. The game name appears in page titles and body text only to identify the subject the tools are about; the site name, logo, navigation labels and domain carry no trademark. Every glyph, mark and social card on the site is drawn here as plain SVG, so no sprites, interface art, item icons or logos from the game are reproduced anywhere.
Where the numbers come from
Fixed mechanics come from the public Old School RuneScape Wiki and are cited page by page in a Sources block that names the article and the year it was reviewed. Nothing is copied as prose: a wiki article is read, the rule is implemented as a pure function, and the function is pinned by a known-answer unit test. Every experience threshold on the site is generated from the standard experience formula rather than transcribed from a table, so level 92 resolving to 6,517,253 XP is a property of the code, not a typo waiting to happen. Combat, damage and probability tools print their equations on the page so a reader can check the arithmetic by hand instead of trusting the output.
Per-skill training methods live in editable JSON data files, one per skill, each carrying action names, level requirements, experience rewards and a dated input-cost snapshot. Keeping them as data rather than code means a correction is a one-line edit that the test suite immediately re-checks.
Prices, snapshots and what stays manual
Prices move far faster than experience values, so no calculator on this site quotes a live market number. Economic fields accept prices you enter yourself, and any stored cost is labelled as a planning snapshot with its review date. That is a deliberate trade: a tool that shows a stale price confidently is worse than one that asks you for the price you can actually trade at.
Corrections and how changes ship
If a value looks wrong, report it through the contact page with the calculator URL, the inputs you used, the result shown, and the source or in-game observation that should replace it. Every change is checked by known-answer unit tests, route-rendering tests, canonical and sitemap coverage checks and a full production build before it is published.