Does anyone know the function which dictates which three of these time-control categories any particular game would fall under? For example, I know that a 3 0 is the quickest blitz game that can be played but I would be unsure whether or not a 2 3 (2 minutes on each persons clock with 3 second increments added) would be blitz or bullet. I'm assuming there is a fairly simplistic formula I could plug these metrics into for a definitive answer but I have yet to stumble upon it.
Thanks ^_^
There is no such globally accepted formula. Time controls are defined only by their formal definitions (as unhelpful as that sounds). Any further descriptive language, like "blitz" or "lightning" or "bullet", while they carry certain conventional connotations, do not have objective criteria. However, certain organizations may define these terms concretely within their own domains.
The USCF defines three time-control zones: Regular, Quick, and Blitz. Different sets of time controls fall into one (or more--it is possible for a game to count as both Regular and Quick, in which case the player's ratings in both categories are affected) of these categories. Determining the category is simple: calculate the [estimated] total playing time (TPT_U) as:
TPT_U = Minutes + SecondsPerIncrement
The TPT_U is then slotted into a zone as follows:
TPT_U > 65: Regular
30 ≤ TPT_U ≤ 65: Regular AND Quick
10 < TPT_U < 30: Quick
5 ≤ TPT_U ≤ 10: Blitz
FIDE defines (as far as I can tell) two time-control zones beyond the standard FIDE time control: Rapid and Blitz. To determine which of these zones a time control falls within, calculate the [estimated] total playing time (TPT_F) as:
TPT_F = Minutes + SecondsPerIncrement
The TPT_F is then slotted into a zone as follows:
10 < TPT_F < 60: Rapid
TPT_F ≤ 10: Blitz
Chess.com defines three time-control zones: Standard, Blitz, and Bullet. To determine which of these zones a time control falls within, calculate the [estimated] total playing time in minutes (TPT_C) as:
TPT_C = Minutes + 2/3*SecondsPerIncrement
This assumes a forty-move game and is derived from the following expression (multiply the increment in seconds by forty, then convert to minutes):
TPT_C = Minutes + (40 * SecondsPerIncrement / 60)
The TPT_C is then slotted into a zone as follows*:
15 ≤ TPT_C: Standard
3 ≤ TPT_C < 15: Blitz
TPT_C < 3: Bullet
*I've had to extrapolate here, as the definition actually appears to leave a gap between 14 and 15 minutes. I've filled this gap in the manner I considered most likely to be accurate.
Base | Incr | TPT_U | TPT_F | TPT_C | USCF | FIDE | CHESS.COM
-----|------|-------|-------|-------|-------|-------|----------
2 | 1 | 3 | 3 | 2.667 | N/A | Blitz | Bullet
3 | 0 | 3 | 3 | 3 | N/A | Blitz | Blitz
3 | 2 | 5 | 5 | 4.333 | Blitz | Blitz | Blitz
5 | 0 | 5 | 5 | 5 | Blitz | Blitz | Blitz
10 | 0 | 10 | 10 | 10 | Blitz | Blitz | Blitz
10 | 1 | 11 | 11 | 10.67 | Quick | Rapid | Blitz
14 | 3 | 17 | 17 | 16 | Quick | Rapid | Standard
TPT is an estimation; it is the same for all games using the given time control. Essentially it assumes that each player makes 60 moves (by adding seconds to minutes as though they shared a unit: equivalent to B minutes + 60*I seconds). I've just added some examples that may clear it up for you.
– Henry Keiter
Nov 5 '14 at 18:39
I do not think that there is a simple formula. It is similar to the paradox between defining heaps of sand or grains of sand. It is difficult to draw the line precisely. If a formula is necessary, I would define it by how much time is used. Assuming that the barriers between blitz and bullet(lightning) is 3 0. A time control can be written as (x,y), for example, (3,0) is the quickest time control for blitz. Let F(x,y)=2x+(4/3)y. The 4/3 was created by the expected time used in a game that last 40 moves(supposedly the average length of a game). F(2,3)=2(2)+(4/3)(3)=4+4=8 Therefore, (2,3) is blitz because it is greater than the boundary defined by F(3,0)=2(3)+0=6 The same can be done for standard chess, but a boundary must be specified.
As if this weren't confusing enough, on ICC there are ratings for
To make matters worse, a game with any of the time controls of 5 minutes or greater can be either in that TC category, or simply a Standard TC game.
So, this seems to be a matter of personal taste at a number of the websites, rather than a case of adhering to FIDE, USCF or any other rules.
By the way, there's also allowable variation in the USCF time controls definitions of regular time controls, but the basic criteria are these (for regular rated games):
The duration of the first time-control must be at least 30 minutes for each player.(However, see (3) below for an exception.)
If a non-sudden death control is used, the rate of play must be equal to or slower than an average of 60 moves per hour.
Rule 5Fa is an option that allows the TD to shorten the basic time control in minutes by the delay in seconds for games using a digital clock with delay. When this option is mandated, the initial control, not the shortened control will govern under which system the event is rated. A G/30 ( 5 second delay) with the control shortened to G/25 for the games using a delay will still be rated in the regular system.
Any secondary controls must be at least 30 minutes.
For FIDE, this is the information I use (a summary taken from USCF reference materials):
1.0 Rate of Play
For a game to be rated each player must have a minimum of two hours in which to complete all the moves, assuming the game lasts 60 moves. Examples of ways this can be achieved follow.
a. The rate of play must not exceed 23 moves per hour at any stage.
b. All the moves in two hours.
c. 40 moves in two hours followed by all the moves in 30 minutes.
d. All the moves in 100 minutes initially, but each time a player makes a move an additional 30 seconds is added to the clock time.
Note that these are minimum conditions; any time control system that a TD implements that is more generous than these conditions require automatically satisfies the regular rating criteria.
