In a close duel, the last thing you want is an arithmetic argument. This life point calculator keeps both players’ totals on one screen — big enough to read across the table — and records every change in a log, so you can always check how you got to the current numbers. It works for any trading card game that tracks life points, from duel-style games starting at 8,000 to games that start at 20 or 40.
How to use the life point calculator
- Choose the starting life points for your game and press New duel. Optionally tap a player’s name to rename them.
- To change a total, type the amount on the keypad — or with your keyboard’s number keys — and press − or + under the right player.
- For common amounts, tap a quick button: −100, −500, −1,000 and +500 for large-number games, or −1, −3, −5 and +1 for small-number games.
- Halve cuts a player’s total in half, rounding up.
- Undo reverses the last change. The duel log lists every change, newest first.
- Need a tie-breaker? Flip a coin or roll a die without leaving the page.
When a player reaches 0, their panel turns red and the other player is shown as the winner.
Life point arithmetic
Each change is a simple addition or subtraction, floored at zero:
The calculator stores each change as “from → to”, which is why Undo can restore the exact previous total even after halving.
Worked example: a three-turn exchange
Both players start at 8,000.
- Player 2 takes a 1,200-point attack: type 1200, press − under Player 2 → 6,800.
- Player 1 pays half their life points for a card effect: press Halve under Player 1 → 4,000.
- Player 2 takes another 1,000 from a quick button → 5,800.
The log now reads, newest first: Player 2 −1,000 → 5,800; Player 1 −4,000 → 4,000 (halved); Player 2 −1,200 → 6,800. If someone disputes the second step, the record is right there.
Typical starting totals
| Starting total | Common use | Quick buttons |
|---|---|---|
| 8,000 | Standard duel-style games | −100, −500, −1,000, +500 |
| 4,000 | Faster “speed” duel formats | −100, −500, −1,000, +500 |
| 40 | Multiplayer or commander-style formats | −1, −3, −5, +1 |
| 30 / 25 | House rules and variant formats | −1, −3, −5, +1 |
| 20 | Standard two-player games with small totals | −1, −3, −5, +1 |
Always confirm the starting total in your game’s official rules or tournament policy; formats change.
Tips for tournament-style play
- Announce every change out loud and wait for your opponent to agree before tapping.
- Keep the screen between you, or let each player track their own total and compare at the end of each turn.
- Use the log at the end of a game to settle disputes instead of recalculating from memory.
- Pick who goes first fairly with the built-in coin flip, or with the full-featured coin flipper. The dice roller handles effects that need more than one die.
This is an independent, unofficial counter and is not affiliated with any trading card game publisher. Card text and official rules always take precedence over the calculator.
Frequently asked questions
How do I subtract damage?
Type the amount on the keypad (for example 1, 2, 0, 0 for 1,200) and press − under the player who takes the damage. Press + instead to gain life points. Quick buttons such as −500 or −1,000 skip the keypad.
How does halving work?
The Halve button cuts a player's life points in half, rounding up when the total is odd, so 4,050 becomes 2,025 and 25 becomes 13. Always follow the exact wording of the card that causes the change.
Can I undo a mistake?
Yes. Undo reverses the most recent change, and you can press it repeatedly to step further back. Every change is listed in the duel log with the new total.
What starting totals are supported?
8,000 and 4,000 for duel-style games that use large numbers, and 40, 30, 25 and 20 for games that count life in small numbers. Quick buttons adjust to the scale you choose.
Will the counter survive a page refresh?
Yes. Life totals, player names and the log are saved in your browser, so an accidental reload or a locked phone does not lose the duel. Press New duel to reset.