Increment (chess): time added after every move
Increment
Definition
In chess time-controls, an increment is a fixed amount of time that is automatically added
to a player’s clock after every move. It is sometimes called a
“Fischer increment” because Bobby Fischer patented the first digital clock with
this feature in 1989. An increment is written after the main time allotment,
e.g. 5 + 3 means each player starts with five minutes and receives three extra seconds
every time they complete a move.
How It Is Used
Modern digital clocks and virtually all online chess servers support increments. They are embedded in every major time-control used today:
- Classical:
90 + 30(FIDE standard) – 90 minutes for the game, 30 seconds added per move. - Rapid:
15 + 10or25 + 5 - Blitz:
3 + 2(most popular blitz control online and over-the-board) - Bullet:
1 + 1or even2 + 1
An increment changes end-game behavior dramatically. Because a player can never run completely out of time as long as moves keep coming, “flag-tricks” become less decisive and technique is emphasized over hand speed.
Strategic Significance
- End-game Technique. Even with a few seconds on the clock, a
30-second increment lets a master convert technical endings. Without
increment (e.g.
5 + 0blitz), a winning side might flag before mating or queening a pawn. - Time-Management Planning. Players often budget their main “bank” time for critical middlegame positions, knowing the increment will sustain them later. A common rule-of-thumb is “think during their move, use the increment to execute yours.”
- Opening Preparation. In bullet or blitz, forcing lines may be prepared to minimize decision-making and harvest the increment, leaving the opponent to burn both bank and bonus time.
Historical Notes
• 1989 – Bobby Fischer files U.S. Patent 4,884,255 describing a digital
clock that adds time after each move.
• Early 1990s –
Increment controls debut in FIDE events once digital DGT clocks appear.
• 1997 – Kasparov vs. Deep Blue used 40/2h + 20/1h + G/30 + 30″
(30-second increment after move 60).
• 2000s – Online platforms popularize short controls like 3 + 2, now the
official FIDE blitz standard.
• 2018 – Carlsen–Caruana World Championship adopted a 30-second increment from
move 1, virtually eliminating time-forfeit losses at the elite level.
Examples
1. In a 90 + 30 classical game, both clocks show 0:30 after 60 moves.
Each player still receives 30 seconds after every subsequent move, so even a
long queen-and-rook ending can be played without the fear of immediate
flagging.
2. Bullet specialists often choose 1 + 1 instead of pure 1 + 0. The extra
second allows a theoretical maximum of 60 moves before either side can flag
(60 × 1″ = 60″), encouraging sharper tactical melees.
Delay vs. Increment
A related but distinct concept is the delay (or “Bronstein delay”). With
delay, a fixed time (commonly 5 seconds) counts down before a player’s main
time starts ticking; unused delay does not accumulate. Increment, by
contrast, always adds to the player’s clock after every move, so time can be
“banked.” The U.S. scholastic scene still favors delay (G/25; d5), while FIDE
events prefer increment (25 + 10).
Interesting Anecdotes
- Fischer’s Vision: During a 1992 television interview, Fischer demonstrated his prototype clock, arguing that increment made adjournments obsolete and guaranteed “real chess.”
-
“Flagging the Engine” – In the early 2000s, some online players
tried to beat computer programs by choosing
1 + 0to outrun them on the clock. Once servers switched to1 + 1, engines became nearly unbeatable even in bullet. -
Longest Increment Game: The 2016 Women’s World Championship
playoff between Tan Zhongyi and Ju Wenjune saw 116 moves in a rapid
game thanks to a
25 + 10control, lasting over an hour despite the modest starting time.
Quick Reference
- Notation:
MainTime + Increment(e.g.,3 + 2) - Invented by: Bobby Fischer (patent 1989)
- First FIDE adoption: Mid-1990s digital-clock era
- Primary purpose: Prevent flagging in winning / drawn positions, promote quality play