--- title: "Double check in chess" url: "https://georgelichess.com/glossary/double-check.md" canonical_url: "https://georgelichess.com/glossary/double-check" last_updated: "2026-11-07" type: "reference" summary: "A double check is a single move that puts the enemy king under attack from two pieces simultaneously, typically one that moved and one it unmasked." related: ["https://georgelichess.com/glossary/discovered-check.md", "https://georgelichess.com/glossary/discovered-attack.md", "https://georgelichess.com/glossary/double-attack.md", "https://georgelichess.com/glossary/royal-fork.md", "https://georgelichess.com/glossary/category/tactics.md", "https://georgelichess.com/glossary.md"] --- # Double check in chess > **For AI agents:** the complete index of GeorgeLiChess pages is [llms.txt](https://georgelichess.com/llms.txt). Every page is also served as markdown at its URL plus .md. A double check is a single move that puts the enemy king under attack from two pieces simultaneously, typically one that moved and one it unmasked. A double check is a single move that puts the enemy king under attack from two pieces simultaneously, typically one that moved and one it unmasked, so only a king move can answer it. The rulebook says a check must be removed, and there are three ways to do it: [capture](https://georgelichess.com/glossary/capture.md) the checker, block its line, or move the king. A double check shuts the first two doors. You cannot capture two pieces with one move, and a single block cannot cover two different lines. Only the king can respond. That is why a double check is so frightening. If the king has no safe [square](https://georgelichess.com/glossary/square.md), the game ends on the spot, and these mates are often the neat final blow of a [combination](https://georgelichess.com/glossary/combination.md). If the king can run, the move still dictates everything, because the opponent has no choice about the reply and you know where the king lands. Most double checks come from a [discovered check](https://georgelichess.com/glossary/discovered-check.md) where the piece that moves also gives check from its new square. So the way to search for one is to start from your discovered check ideas and test each landing square of the mover for a check of its own. [Knights](https://georgelichess.com/glossary/knight.md) make ideal movers, because a knight check lands from a distance. To protect yourself, give the king breathing room with luft, avoid standing in a line behind your own piece when an enemy rook or [bishop](https://georgelichess.com/glossary/bishop.md) is aimed there, and watch your king's flight squares before pieces crowd around it. In the diagram White plays Nc7#. The knight checks from c7 and uncovers the rook on e1, so the king on e8 is attacked twice. The rooks on d8 and f8 and the pawns on d7 and f7 box the king in. ## Example position White to move plays Nc7#. The knight checks the king on e8 and uncovers the rook on e1 for a second check, and the king has no flight squares, so it is mate. Position (FEN): `3rkr2/3p1p2/4N3/8/8/8/8/4R1K1 w - - 0 1` It sits close to [Blackburne's mate](https://georgelichess.com/glossary/blackburnes-mate.md). Blackburne's mate is a checkmate made with two bishops and a knight, where a bishop checks on h7 guarded by a knight on g5 while the other bishop on the long diagonal covers g7 and h8. A neighboring idea is [Greek gift sacrifice](https://georgelichess.com/glossary/greek-gift-sacrifice.md). The Greek gift sacrifice is a bishop sacrifice on h7, or h2 for Black, played as Bxh7+ Kxh7, followed by a knight check on g5 and the queen coming to the h-file to attack the exposed king. Also worth reading is [Royal fork](https://georgelichess.com/glossary/royal-fork.md). A royal fork is a fork that attacks the enemy king and queen at the same time, most often with a knight, so the king must move and the queen is lost. To see how often "Double check" or a pattern like it decides your own games, book a [first lesson](https://georgelichess.com/book/first-lesson.md): George Li reviews your games and writes a study plan around what he finds. ## Related terms - [Discovered check](https://georgelichess.com/glossary/discovered-check.md) - [Discovered attack](https://georgelichess.com/glossary/discovered-attack.md) - [Double attack](https://georgelichess.com/glossary/double-attack.md) - [Royal fork](https://georgelichess.com/glossary/royal-fork.md) ## Guides that go further - [How to choose a chess coach](https://georgelichess.com/how-to-choose-a-chess-coach.md): What to decide first, the questions to ask, what a first lesson should show and the red flags to avoid. - [How much does chess coaching cost?](https://georgelichess.com/chess-coaching-cost.md): Published rates for private, group and subscription chess coaching, with the source and the date of each. - [The first lesson](https://georgelichess.com/book/first-lesson.md): A game review, a read on your level and a written study plan from George Li. [Book your first lesson](https://georgelichess.com/book.md) and George Li reviews your games and builds a study plan around them. Questions about lessons: write to hello@georgelichess.com. ## Related - [Discovered check in chess](https://georgelichess.com/glossary/discovered-check.md) - [Discovered attack in chess](https://georgelichess.com/glossary/discovered-attack.md) - [Double attack in chess](https://georgelichess.com/glossary/double-attack.md) - [Royal fork in chess](https://georgelichess.com/glossary/royal-fork.md) - [Chess terms: Tactics and combinations](https://georgelichess.com/glossary/category/tactics.md) - [Chess terms glossary: plain definitions](https://georgelichess.com/glossary.md)