bet365
Bet £10 Get £30 In Free Bets
Open Account Offer – New Customers only. Bet £10 and get £30 in Free Bets when you join bet365. Sign up, deposit between £5 and £10 to your account and bet365 will give you three times that value in Free Bets when you place qualifying bets to the same value settle. Free Bets are paid as Bet Credits. Min odds/bet and payment method exclusions apply. Returns exclude Bet Credits stake. T&Cs apply. #Ad. 18+
BetMGM
Bet £10 Get £40 In Free Bets
New customers: Deposit £10+ within 7 days and place a sports bet. Get 4 x £10 Free Bets (2 x £10 Bet Builders & 2 x £10 Sports Bet). Valid 7 days. Min odds apply. Excludes virtual sports, esports and non-UK/IE horse racing. #Ad. 18+ T&Cs apply.
Betfred
Bet £10 Get £50 in Free Bets
New customers only. Register, deposit with Debit Card, and place first bet £10+ at Evens (2.0)+ on Sports within 7 days to get 3 x £10 in Sports Free Bets & 2 x £10 in Acca Free Bets within 10 hours of settlement. 7-day expiry. T&Cs Apply.
BetUK
Bet £10 Get £40 In Free Bets
New customers: Deposit £10+ within 7 days and place a sports bet. Get 4 x £10 Free Bets (2 x £10 Bet Builders & 2 x £10 Sports Bet). Valid 7 days. Min odds apply. Excludes virtual sports, esports and non-UK/IE horse racing. 18+. T&Cs apply. Acca Club: Available to new & existing customers. 3 or more selections. Min Odds: 3/10 (1.3) per leg. Max stake: £500. Max Winnings: £200,000 per boost. Profit Boost amounts vary. Horse Racing, Greyhounds & Trotting excluded. Exclusions apply. 18+. T&Cs apply.
LiveScoreBet
Bet £10 Get £30 In Free Bets
New members only. £10+ bet on sports (ex. Virtuals) 1.5 min odds, settled within 14 days. Free Bets: accept in 7 days, valid 7 days. Stake not returned. T&C’s Apply #Ad. 18+
10Bet
100% up to £50 on first deposit
New bettors. Select bonus at signup or use code SPORT. Wager deposit & bonus 8x. Valid 60 days. Odds, bet & payment limits apply. T&Cs Apply; 18+ #Ad.
Virgin Bet
Bet £10 Get £30 In Free Bets
New members only. £10 min deposit & bet on sportsbook, 1.5 min odds in 14 days. Free Bets: accept in 7 days, valid 7 days, stakes not returned. T&Cs Apply. #Ad. 18+
EasyBet
Bet £20 Get £20 In Free Bets
New customers only. To qualify for free bets, the new user must place and settle £20 on easyBet markets. The user must bet on at least 2 different events to qualify. The user must place and settle bets at odds of 2.0 or more. An event is classed as two different sporting events. Bets can be placed on singles, multiples and Bet Builders. The user must place and settle bets before the closing date of the promotion to qualify. Users making their first deposit by Skrill, Neteller or PaySafe card will not qualify for this promotion. T’s and C’s Apply. Be Gamble Aware.
18+•#Ad•Please gamble responsibly
1. Odds Converter
Convert between formats and see the implied probability instantly.
Implied Market Probability:
50.00%
2. Kelly Criterion Calculator
%
Recommended Stake
10.00%
The Professional Guide to Kelly Criterion & Odds
If you want to move from a casual bettor to a profitable one, understanding bankroll management is more important than picking winners. The Kelly Criterion is the gold standard for sizing bets in sports betting, stock trading, and advantage play.
1. Finding “Value” with the Odds Converter
A “Value Bet” occurs when the probability of an outcome is higher than the probability suggested by the bookmaker’s odds. Use our converter to find the market’s expectation:
- Decimal Odds: Divide 1 by the odds (e.g., $1 / 2.00 = 0.50$ or 50%).
- American Odds: For positives, $100 / (Odds + 100)$. For negatives, $Odds / (Odds + 100)$.
If your research suggests a team has a 60% chance to win, but the odds converter shows an implied probability of 52%, you have a 8% edge.
2. Kelly Strategy Comparison
| Method | Risk Level | Best For |
|---|---|---|
| Full Kelly | High | Maximum growth, high volatility. |
| Half Kelly | Moderate | Professional standard balance. |
| Quarter Kelly | Low | Long-term safety & beginners. |
3. The Math Behind the Magic
The formula $f^* = (bp – q) / b$ ensures that you never go broke while betting. Because the stake is a percentage of your current bankroll, your bet sizes decrease during a losing streak and increase during a winning streak, providing a built-in “compounding” effect.
Warning: The biggest risk with the Kelly Criterion is “Overestimation Bias.” If you think your win chance is 60% but it’s actually 52%, betting Full Kelly will eventually lead to bankroll depletion. Always be conservative with your “Win Chance” estimates.
Frequently Asked Questions
Can Kelly Criterion be used for Parlays?
Yes, but the win probability drops significantly, and the odds (b) increase. The formula remains the same, but the recommended stake will usually be much smaller.
Yes, but the win probability drops significantly, and the odds (b) increase. The formula remains the same, but the recommended stake will usually be much smaller.
What if the calculator says “No Value”?
This means the bookmaker’s margin (the “vig”) has eaten your edge, or the odds are too low for your estimated win chance. In this scenario, the mathematically correct bet is $0.
This means the bookmaker’s margin (the “vig”) has eaten your edge, or the odds are too low for your estimated win chance. In this scenario, the mathematically correct bet is $0.
