Frequently asked questions

Please see the Contact page for details.

InARow uses the Glicko-2 rating system (read more on Wikipedia), a version of the ELO system used in chess. Your rating is a number that shows how strong you are compared to other players.

• Everyone starts at 1500. While the system is still getting to know you, your rating shows a question mark (for example 1500?) and moves a lot after each game. After about a dozen rated games it settles and the "?" disappears.
• Win and your rating goes up; lose and it goes down. Beating a stronger player earns you more than beating a weaker one.
• Moving first (Red) is a big advantage in 4-In-A-Row, so the ratings consider it: Red is treated as a little stronger than their actual rating. So, Red earns slightly less for a win, Yellow earns slightly more, and a draw costs Red a few points. This rating impact is more significant in games between stronger players, who can make better use of moving first.
• You have a separate rating for each time control.
• Only rated games count. Games against a friend, unrated games, aborted games and games on your own device never change your rating.
• During a rated game, next to your rating, you can see exactly how much you would win or lose, for example (+8.2 / −2.7 / −13.6) for a win, a draw or a loss.
• The same two players can play at most 3 rated games against each other in 24 hours. After that, their rematches are unrated.

That's right, if both players play perfectly then Player 1 (Red) will always win. This means that going first is a significant advantage, even for imperfect (human) players. We take this into account in a two ways:

• The matchmaking system for rated games is set up so that whichever player has been Red (Player 1) more often in the last 10 games will play as Yellow (Player 2). This makes sure that, over time, you'll have an even amount of games with each colour. Rematches always swap the colours.
• The ELO system is set up such that when working out what result to expect, Red is treated as a little stronger than their actual rating. So, Red earns slightly less for a win, Yellow earns slightly more, and a draw costs Red a few points. This rating impact is more significant in games between stronger players, who can make better use of moving first.

• Connect 4® is Hasbro’s brand of the traditional game 4-In-A-Row. InARow isn’t connected with Hasbro.

• Players who consistently play the best moves according to the solver, especially in obscure situations, will be flagged for a cheating review.
• To prevent rating farming, games set up as a challenge between friends are always unrated. Also, you can only play a maximum of 3 rated games against a single opponent within a 24 hour period before being unable to matchmake with them again. Any rematches are also unrated.

4-In-A-Row is a solved game: for any position, a computer can work out exactly what happens with perfect play from both sides. After every finished game, Game Review uses a solver to check every move you made.

Each move is compared with the best move available at that point, and given one of these labels:

• Great: the only good move in a difficult position. Every other move would have thrown away your win or your draw, and it wasn't an obvious move.
• Best: the best move. If several moves were equally good, any of them count as Best.
• Good: a respectable move. You're still winning, but there was a quicker win available.
• Inaccuracy: you were already losing (against perfect play), and this move lets your opponent win sooner than necessary.
• Mistake: you were already losing, and this move lets your opponent win on their very next move, when you could have held out for longer.
• Missed win: there was a winning move, but this one only draws.
• Blunder: gives your opponent a chance to win. You had a win or a draw, and after this move you're losing.

"Winning" and "losing" here mean against perfect play. Real opponents make mistakes, so a "losing" position can still be saved, which is why holding out for longer matters.

Each of your moves gets a score, and your accuracy is the average:

• Great and Best: 100%.
• Good: 100%, minus 10% for each extra move your win now takes (but never below 50%). For example, a move that wins in 4 moves when you could have won in 2 scores 80%.
• Inaccuracy: 100%, minus 10% for each move sooner your opponent can now win (but never below 50%).
• Mistake: 25%.
• Missed win: 20%.
• Blunder: 0%.

So slower wins cost a little, and moves that throw away a result cost a lot.