Understanding bet sizes and raises
Content by Tools of Poker Methodology and calculation assumptions
What does this calculation help you do?
At the table, a percentage, a raise total and the chips you must add describe different amounts. This exercise helps you translate between them, follow the action and recognize a legal full raise. It prepares you for pot odds and EV calculations, where counting an earlier contribution twice changes the answer.
One round follows one heads-up river hand through three questions. Both players have enough chips. Hero opens the betting, the opponent raises and Hero considers another raise. The percentages and proposed sizes are supplied for arithmetic practice; you are not selecting a strategic bet size.
1. Convert a percentage of the pot into BB
There are 20 BB in the initial pot. Hero plans to bet 25 percent of that pot. Divide the percentage by 100 and multiply by the initial pot: the bet is 5 BB.
20 × 25 ÷ 100 = 5 BB
Think of the percentage as a fraction of the pot: 25 percent is one quarter, 50 percent is one half and 75 percent is three quarters. For a 20 BB pot, a quarter is 20 divided by 4: 5 BB. This percentage describes the bet size, not your chance of winning or how often you should bet.
The percentage is a supplied proposal. This reference table illustrates common sizes using the same 20 BB initial pot. A size above 100 percent is an overbet, allowed here when the stack is sufficient.
| Percentage of the initial pot | Opening bet (BB) |
|---|---|
| 25% | 5 |
| 50% | 10 |
| 75% | 15 |
| 100% | 20 |
| 125% | 25 |
| 150% | 30 |
2. Distinguish a raise total from new chips
Hero has bet 5 BB. The opponent raises to 13 BB. Hero now considers raising to 25 BB in total. Hero’s earlier 5 BB already count toward 25 BB, so the new contribution is 20 BB. Subtract Hero’s own contribution, not the opponent’s 13 BB.
25 − 5 = 20 BB
You can also split the new contribution into two parts. First match the opponent: 13 minus your existing 5 BB costs 8 BB. Then increase that total from 13 to the proposed 25 BB: another 12 BB. Together you add 20 BB. The 12 BB raise increment alone would not reach the announced total.
(13 − 5) + (25 − 13) = 8 + 12 = 20 BB
At this point the current pot is 38 BB: the initial 20 BB, Hero’s 5 BB and the opponent’s 13 BB. The opponent had contributed nothing on this street before raising, so adds the full 13 BB. The raise increment of 8 BB is a different quantity. Hero’s proposed new raise has not entered the pot.
3. Find the minimum legal raise-to total
Rule 45 explained: the size of a full raise
In no-limit play, a full raise must increase the current wager by at least the largest previous full bet or raise increment on this street. A declared raise amount is the new total. The minimum follows the last full increment, not an automatic doubling of the current total.
The opponent increased the wager from 5 BB to 13 BB, an increment of 8 BB. Hero’s next full raise must increase 13 BB by at least another 8 BB. The minimum total is therefore 21 BB. The proposed 25 BB total from the previous question is above that minimum.
13 + (13 − 5) = 21 BB
The question asks for the new total of 21 BB. If Hero chose that minimum, the additional chips would be 21 minus the 5 BB already committed: 16 BB. Distinguish the 8 BB raise increment, the 21 BB new total and the 16 BB Hero would add.
Compare three possible amounts from the same decision. Hero has already bet 5 BB and faces 13 BB. Calling, making the minimum raise and raising to the proposed 25 BB require different new contributions. The exercise asks for the proposed contribution in question 2 and the minimum total in question 3.
| Action | Hero’s final total on this street (BB) | New chips Hero adds (BB) |
|---|---|---|
| call | 13 | 13 − 5 = 8 |
| Minimum full raise | 21 | 21 − 5 = 16 |
| Proposed raise | 25 | 25 − 5 = 20 |
The minimum is a floor, not a required size. With enough chips, 21 BB, 22 BB or 25 BB are all full legal totals here. A non-all-in raise to 20 BB adds only 7 BB above 13 BB, below the required 8 BB increment.
Minimum full raise: 21 − 13 = 8
Proposed raise: 25 − 13 = 12 ≥ 8
Rule 49 explained: when betting reopens
A short all-in can increase the amount to call without reopening a raise for someone who has already acted. To regain the right to raise, that player must face at least a full increase since their last action. Several short all-ins can reach that threshold together. The minimum still uses the last full increment.
The practice rounds use two players and full raises. The following examples use more players only to explain reopening; no extra exercise step is added.
Example: a short all-in does not reopen betting
Hero bets 5 BB, B calls 5 BB and C goes all-in for 8 BB. Hero now faces 3 BB more, less than the full 5 BB increment. Hero can fold or call the extra 3 BB, but cannot raise when the action returns.
Example: short all-ins together reopen betting
Hero bets 5 BB, B goes all-in for 8 BB, C goes all-in for 10 BB and D calls 10 BB with chips left. Hero faces a combined 5 BB increase, so can raise again. The minimum total is 15 BB: the current 10 BB plus the last full 5 BB increment.
10 + 5 = 15 BB
Keep two checks separate: whether you are allowed to raise again, and the smallest full raise total if you are. In the exercise, action is always open for Hero after the opponent’s full raise, so you only calculate that total.
Use the bet actually made after rounding
With a 10.05 BB initial pot and a 33 percent bet, the calculation gives 3.3165 BB. Round to 3.32 BB. If the opponent then raises to 8.50 BB, the last increment is 5.18 BB and the next minimum total is 13.68 BB. Later answers use the actual 3.32 BB bet.
8.50 + (8.50 − 3.32) = 13.68 BB
How to practise this exercise
Every difficulty asks the same three questions in the same order on one hand. Beginner/easy show full formulas and real numeric substitutions; intermediate keeps symbolic formulas; difficult/nightmare remove hints. The table shows the opening proposal first, then the actual bet and opponent raise. Final results explain all three calculations.
The whole round allows 240, 210, 150, 100 or 75 seconds from beginner to nightmare. Answer counts are three, three, four, four and five per question. Earlier wrong answers do not change later grading. Without JavaScript, all three questions and their scenario inputs are available in a native form.