bettorstack
US UK

▌ Day 13 · launched 2026-04-26 · 9 calculators live

Calculators
that show
their work.

Action Network's organic search traffic dropped 47% over the past thirteen months. Sportsbookreview lost 41%. AceOdds lost 46%. The "best sportsbooks" listicles those affiliate sites built their revenue on got replaced by AI Overviews — and the math survived.

Twenty-four calculators across US and UK markets. Every formula derived from a primary source. The math sits on the page below the calculator on every page. That is the entire pitch.

Read methodology About BettorStack
9
Calculators live
US + UK
Markets
0
Affiliate listicles
13
Day

▌ US Tier A · 9 calculators live

Start calculating

Risk management

Hedge Calculator

Lock guaranteed profit or cut losses on an open bet. Per-leg stake allocation.

Two-book arb

Arbitrage Calculator

Find and size cross-book arbitrage opportunities. Detects arb automatically.

Format conversion

Odds Converter

American ↔ decimal ↔ fractional ↔ implied probability. All four at once.

Strip the margin

No-Vig Calculator

Remove bookmaker overround to find true implied probability on any line.

Bet return

Payout Calculator

Calculate total payout, net profit, and ROI for any stake and odds.

Matched betting

Bonus Bet Calculator

Convert sportsbook free bets to guaranteed cash with the SNR lay formula.

Edge detection

Implied Probability Calculator

Extract the win percentage embedded in any odds line. Find where you have edge.

Fair pricing

Implied Odds Calculator

Start from a probability estimate — get the fair American, decimal, and fractional line.

Card equity

Poker Odds Calculator

Outs, pot odds, and equity — Texas Hold'em hand-to-hand math.

[ Original math ]

Kelly criterion derives from Kelly's 1956 paper in the Bell System Technical Journal. Vigorish from the standard 2-way fair-odds derivation. UK accumulator bonuses from each bookmaker's own published rule book.

Every formula is shown on the page. No black-box "trust the calculator" math.

[ Per-state US tax ]

US gambling winnings face 24% federal withholding above thresholds, plus state-specific rates that vary widely — NY 8.82%, NJ 3%, CA exempt-but-reportable, Florida none.

Most calculator sites stop at the gross payout. We show post-tax net per state, sourced from IRS Publication 525 and the relevant state tax authority.

[ UK bookmaker bonuses ]

William Hill pays a 10% bonus on total returns when all four selections in a Lucky 15 win (double odds when only one wins). Paddy Power pays 30% when all four land. Coral, Ladbrokes, Sky Bet each have their own rule book — and Rule 4 deductions apply across all of them on horse-racing markets.

The UK calculators encode every published rule. No competitor does this.

Frequently asked

05 / questions
Q01 Why does BettorStack exist?
Action Network's organic search traffic dropped 47% in the past thirteen months. AceOdds dropped 46%. Sportsbookreview lost 41%. The "best sportsbooks" content those sites built revenue on got replaced by AI Overviews. The math survived. BettorStack publishes the math without the affiliate listicle layer that broke.
Q02 How is BettorStack different from AceOdds or OddsJam?
Three differences. First, every formula is cited to a primary source — Kelly's 1956 Bell System Technical Journal paper, the standard vigorish derivation, each UK bookmaker's published rule book. Competitors show results, not derivations. Second, US calculators include per-state tax math (federal 24% withholding plus state-specific rates). Most calculator sites stop at gross payout. Third, UK calculators encode bookmaker-specific bonuses: William Hill Lucky 15 all-4-winners pays 10% on total returns (1 winner: double odds), Paddy Power 4-from-4 pays 30% bonus — none of the existing UK sites encode these.
Q03 Which calculators are live now?
Nine US Tier A calculators are live as of May 2026: hedge calculator, poker odds, no-vig, odds converter, payout calculator, bonus bet calculator, arbitrage calculator, implied probability calculator, and implied odds calculator. UK Tier A (Lucky 15, Patent, Matched Betting, Free Bet, Each Way — five calculators) ships June 2026.
Q04 How does BettorStack make money?
Single inline affiliate CTA per calculator page, FTC-compliant disclosure adjacent. Programs: Bet365 Partners, OddsMonkey (50% recurring × 12 months), William Hill, Paddy Power, Stake.com, Adsterra display fallback. No AdSense — AceOdds (industry leader) verifiably runs zero AdSense, and Google's March 2026 stricter per-country gambling certification makes AdSense not worth the friction. UK pages run with no affiliate links for the first six months — pure-calculator service sits within the UK Gambling Commission's affiliate carve-out.
Q05 Is this UKGC licensed?
Not yet, and not required for the first six months. The UK Gambling Commission's affiliates guidance carves out tools that do not promote specific operators. As long as UK calculator pages do not carry bookmaker affiliate links, no UKGC licence is needed. UK affiliate links roll out late 2026 with full UKGC-compliant disclosure on every link, after the calculator pages have indexed and built initial authority.

/uk/ — launching June 2026

Browsing from the UK?

Dedicated UK calculator hub at /uk/ with Lucky 15, Patent, Matched Betting, Each Way and the rest of the accumulator family — tailored to UK bookmaker rules.

Visit /uk/