# Casinoly Slots > Free slot calculators for US players: wagering requirements, session and bankroll length, RTP and volatility, each with the formula and a plain-language guide. Independent site, not operated by any casino. It lists no casino offers. Calculators run in the browser and show their formulas; the simulators use described model slots, not real games. ## Wagering Requirement Calculator - [Wagering Requirement Calculator](https://casinolyslots.com/wagering-calculator/): Work out how much you must bet to clear a casino bonus, what that play costs on average at the game's RTP, and how long it takes. Formula and examples included. - [What a Playthrough Requirement Means](https://casinolyslots.com/wagering-calculator/playthrough-requirements/): A playthrough requirement is the total you must bet before bonus money can be withdrawn. How it is counted and what bonus only versus deposit plus bonus means. - [Game Contribution and Why Slots Usually Count in Full](https://casinolyslots.com/wagering-calculator/game-contribution/): Game contribution sets how much of each bet counts toward a bonus playthrough. How it multiplies the betting you need, why casinos weight games, what to check. - [The Bonus Rules the Calculator Cannot See](https://casinolyslots.com/wagering-calculator/bonus-rules/): Expiry windows, eligible games, bet limits, the order funds are used and cancellation rights. The casino bonus terms that decide whether you keep what you win. - [How Regulated US Casino Bonuses Are Structured](https://casinolyslots.com/wagering-calculator/us-bonus-terms/): In states that license online casinos, bonus terms are filed with the regulator, must state the playthrough by game type and cannot cap cleared winnings. - [Is a Casino Bonus Worth It? How to Work Out Its Value](https://casinolyslots.com/wagering-calculator/bonus-value/): A casino bonus is worth roughly the bonus minus the house edge on the play needed to clear it. Six common bonus shapes worked through, plus what that misses. ## Slot Session and Bankroll Calculator - [Slot Session and Bankroll Calculator](https://casinolyslots.com/session-calculator/): See how many spins and how much time a slot bankroll buys on average, the expected loss per hour, and how widely real sessions vary. Formula and examples. - [Expected Loss Per Hour on Slots](https://casinolyslots.com/session-calculator/loss-per-hour/): Expected loss per hour on a slot is bet times spins per hour times the house edge. How to work it out, why pace matters as much as RTP, and how to use it. - [Choosing a Bet Size for Your Slot Bankroll](https://casinolyslots.com/session-calculator/bet-size/): Your bet size decides how long a slot bankroll lasts and how often you go broke early, not the house edge. How to size a bet, with simulated survival odds. - [How Fast Slots Play, and Why Speed Costs Money](https://casinolyslots.com/session-calculator/spin-speed/): Spin speed multiplies what a slot session costs: twice the spins per hour means twice the expected loss. How to measure your pace and what the rules say. - [Setting Session Budgets and Loss Limits](https://casinolyslots.com/session-calculator/session-limits/): Licensed US online casinos must let you set deposit, spend and time limits. How those limits work, how fast a change takes effect, and how to size one. ## RTP and Volatility Simulator - [RTP and Volatility Simulator](https://casinolyslots.com/volatility-simulator/): Simulate a slot session on low, medium and high volatility model games at the RTP you choose, and see how widely results spread around the average loss. - [What RTP Means on a Slot](https://casinolyslots.com/volatility-simulator/what-rtp-means/): RTP is the share of all money bet that a slot is designed to pay back over its full cycle. How it is defined, the US state minimums and why RTPs vary. - [Slot Volatility Explained](https://casinolyslots.com/volatility-simulator/slot-volatility/): Volatility describes how a slot spreads its return, in many small wins or a few large ones. What it does to a session, how it is measured and how to spot it. - [Hit Frequency and Why Many Slot Wins Are Losses](https://casinolyslots.com/volatility-simulator/hit-frequency/): Hit frequency is the share of spins that pay anything, but many of those wins pay back less than the bet. How it relates to RTP and volatility, with examples. - [Why RTP Only Shows Up Over Many Spins](https://casinolyslots.com/volatility-simulator/short-run-vs-long-run/): A slot's cost grows with every spin, but the swing around it grows only with the square root of the spins. Why one session tells you almost nothing about RTP. ## Slot Terms Glossary - [Slot Terms Glossary](https://casinolyslots.com/slot-terms/): Plain-English definitions of the slot and bonus terms our calculators use, from playthrough and game contribution to RTP, house edge and volatility. ## About Casinoly Slots - [About Casinoly Slots](https://casinolyslots.com/about/): Casinoly Slots publishes free slot calculators for US players, with plain-language guides. Independent, not run by any casino, and it lists no casino offers. ## Editorial Policy - [Editorial Policy](https://casinolyslots.com/editorial-policy/): How Casinoly Slots researches its guides, how the calculators and model slots work and were tested, their limits, and how we handle links to sister sites. ## Responsible Gambling - [Responsible Gambling](https://casinolyslots.com/responsible-gambling/): Free, confidential help for US players: the 1-800-MY-RESET helpline, Gamblers Anonymous, state self-exclusion, casino limit tools and the warning signs.