About LineMath

LineMath is a set of fast, free, no-signup betting calculators for US bettors — built so the numbers are right.

Why it exists

Most betting calculators are buried in ad-heavy content pages, slow on mobile, and quietly wrong in places. LineMath does one thing: put an exact answer on screen the instant you type, with no account, no paywall, and no clutter.

How we keep the math right

• Every calculator runs entirely in your browser. Your stakes and odds are never sent to a server.
• All odds, parlay, hedge, bonus-bet, no-vig, EV, Kelly, and arbitrage formulas live in one shared, unit-tested library.
• Tests check known answers to the cent — for example, three -110 legs must pay $695.79 on a $100 stake, and a $100 bonus bet at +200 hedged at -220 must convert to 62.5% in cash.
• Bonus bets are modelled correctly: a free bet does not return its stake, a mistake that overstates conversion on many other sites.
• Inputs that can't produce a valid result show an inline message — never a blank or NaN.

What we are not

LineMath is not a sportsbook, doesn't accept bets, and doesn't give betting advice. Results are informational and educational; payouts can differ from what your sportsbook settles, so always verify with your book. Some pages link to sportsbooks, and we may earn a commission — see our advertising disclosure.

Play responsibly

You must be 21+. If gambling is a problem, call 1-800-GAMBLER. More on our responsible gambling page.