TabletopCalc started at a game table, mid-argument, when nobody could agree on how much experience a fight was worth or whether a Monopoly trade was actually fair. The math was buried in the rulebooks, but digging it out slowed the game to a crawl. This site is the fix: fast, accurate calculators for the numbers that come up when you actually play, with the reasoning shown so you can trust the answer instead of taking it on faith.
The site is organised around two kinds of pages. The calculators handle the arithmetic that interrupts a game in progress: damage per round in Dungeons and Dragons 5th Edition, attack math and treasure targets in Pathfinder 2e, army points in Warhammer 40,000, mana curves and land counts in Magic: The Gathering, pack value in Yu-Gi-Oh, One Piece, and Star Wars Unlimited, trade fairness in Monopoly, deduction in Clue, and word scoring in Scrabble and Words With Friends.
The guides go the other direction. Instead of returning a number, they explain the system underneath it, so you can make better decisions without a tool open in front of you. Each calculator page also carries a written explanation of its own math, including a worked example you can follow with a pencil if you want to check the result yourself.
Every calculator starts from the published rules of the game it serves, not from a rule of thumb picked up on a forum. That means the official rulebooks and reference documents, the freely available System Reference Document for Dungeons and Dragons, current points and costing values for miniature and card games, and the standard probability math for dice and board movement.
Three principles guide the work. First, show the formula. If a tool tells you your damage per round is 15, the page explains how it reached 15, so you can spot an input you entered wrong. Second, say when a number is a guideline rather than a rule. Game designers publish recommended treasure totals and encounter budgets that are meant to be adjusted, and the guides label them as such instead of presenting them as law. Third, prefer the boring, verifiable answer over the exciting one. If the honest response to a question is that it depends on your table, the page says so.
Games change. Points values get updated between seasons, card sets rotate, prices move with the competitive scene, and errata quietly rewrite a rule that a calculator depended on. When that happens the affected tool and its explanation are updated together, so a page never explains one thing while the calculator does another.
If you find a result that looks wrong, please say so. A reproducible example, meaning the inputs you used and the answer you expected, is the fastest way to get something fixed. Corrections from readers who play these games closely have improved more than one tool here.
TabletopCalc is free to use. There are no accounts, no subscriptions, no paywalled tools, and nothing to install or download. The tools run entirely in your browser, and advertising covers the hosting and the time it takes to research and maintain them.
Advertising never determines what the tools say. A pack value calculator that told you sealed product was always a good buy would be worthless, and worse, dishonest, so the math reports what it reports even when the answer is that you should buy the single instead.
TabletopCalc is written and edited by Reid Calloway, a longtime tabletop and role-playing game player who would rather roll dice than do arithmetic. He builds these calculators and writes every guide from official rulebooks and published game math, so the numbers stay transparent and easy to check.
Suggestions for a new calculator are genuinely welcome. Most of the tools here exist because a game slowed to a halt over a question nobody could answer quickly, which is exactly the kind of problem worth automating. Ideas and corrections can go to the contact page.
TabletopCalc is an independent fan resource, not affiliated with or endorsed by any game publisher, and all game names and trademarks belong to their respective owners.