Perp

Perp is shorthand for perpetual check, a repeating series of checks that forces a draw by repetition.

Category
Tactics
Also in
Rules, Strategy
Difficulty
Intermediate
Also known as
perpetual check, perpetual, perp check

Perp is shorthand for perpetual check, a drawing resource in which one side forces an endless series of checks that the opponent cannot avoid.

The checks must cycle through the same position at least three times, allowing the player to claim a draw by repetition under the rules. Because the checked side is never allowed a move that breaks the cycle, the game cannot progress and ends drawn.

A perp usually appears when the defender is materially behind or under a mating attack. Instead of trying to win back material or defend passively, the defender switches to a series of forcing checks that keep the enemy king moving and prevent any counter-threat from being executed.

Typical patterns include a queen oscillating between two checking squares on an open file or diagonal, or a rook checking along a rank while protected by its own king or pawns. The key requirement is that every reply by the opponent still leaves another check available on the next move.

Club players often miss perps because they stop calculating once they see the first check. Training yourself to look one or two checks deeper in desperate positions frequently reveals a saving perp that turns a loss into a half-point.

Related ideas include threefold repetition, the formal rule that converts the checks into a draw, and draw by repetition, the broader category that also covers non-checking cycles.

Frequently asked questions

What does "perp" mean in chess?
Perp is shorthand for perpetual check, a drawing resource where one side forces an endless series of checks that the opponent cannot escape.
How does a perpetual check produce a draw?
The checks must cycle through the same position at least three times, allowing the player to claim a draw by repetition under the rules.
When is a perp most often used?
A perp usually appears when the defender is materially behind or facing a mating attack and needs to force a draw instead of losing.
Which pieces commonly deliver perps?
Queens or rooks are typical, oscillating between checking squares on open files, ranks, or diagonals while the opponent has no way to break the cycle.
Why do club players often miss perps?
They stop calculating after the first check instead of looking one or two moves deeper in desperate positions where a saving sequence may exist.

See also

  • Check — Check occurs when a player's king is under direct attack by an opponent's piece and must be resolved on the next move.
  • Checkmate — Checkmate ends the game when a king is in check and has no legal way to escape by moving, capturing the attacker, or blocking the attack.
  • Dead Draw — A dead draw is a position offering neither side any realistic winning chances even against suboptimal defense, typically from insufficient material or blocked structures that prevent all progress.
  • Discovered Check — A discovered check occurs when one piece moves aside, revealing an attack on the enemy king from a second piece positioned behind it on the same line.
  • Double Check — A double check occurs when two pieces simultaneously check the enemy king, most often via a discovered check in which the moving piece also attacks the king.
  • Drawing Weapon — A drawing weapon is an opening line or variation deliberately chosen to maximize the likelihood of forcing a draw, especially when a half-point is the priority.

Written by Chesswick.

Reviewed by James Duprey.

Published
Last updated

About the reviewer

James Duprey

James came to chess late, and he'll tell you that's part of the appeal. He picked up the game in his thirties, mostly out of boredom, and found something he wasn't expecting: a puzzle that never quite runs out of new…

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