Chase an IM Norm Through a Nine-Round Open

Few things in chess are as tense as the last rounds of an open with a norm in sight. Players, coaches and parents all try to work out what is needed, usually on the back of a scoresheet. The arithmetic is not difficult, but it depends on opponents you have not yet met. This guide follows one player through the second half of a nine-round open, using the norm and performance calculators, and covers the requirements that decide whether a good result actually counts.

The position after five rounds

A player rated 2395 has scored 4 out of 5 against opponents rated 2385, 2290, 2402, 2260 and 2350: three wins and two draws. The performance calculator gives an average of 2337 and a 2577 performance so far, well above the 2450 needed for an International Master norm. But the norm is judged over the whole event, and four games remain.

Step 1: estimate the full field

The average opponent rating for the norm is calculated over all nine games. The pairings for the remaining rounds are not known, but a player on 4/5 in a strong open can expect to meet opponents near the top of the field. Suppose the next four opponents are rated about 2400, 2330, 2370 and 2280. The nine-game average is then 2341, comfortably above the 2230 minimum for an IM norm.

Step 2: the score needed

The norm calculator, with an average of 2341 over nine games, shows that 6 points is enough. 6/9 is 67%, giving dp = +125 and a performance of 2466 against the 2450 required. 5½ would be 61%, dp = +80, a performance of 2421, not enough. So the player needs 2 points from the last 4 games: two wins, or a win and two draws, or four draws. Entering a score of 4 from 5 games played confirms it: 2 more from the remaining 4 games.

Step 3: what if the pairings are weaker?

If a loss in round 6 sends the player down to face weaker opponents, the average falls. Suppose the last opponent is rated 2180 instead of 2280: the average becomes 2330, and 6/9 still gives 2330 + 125 = 2455, just enough. But if the average drops much further, 6 points may not be enough, and below 2230 average no score qualifies. Rating floors in the FIDE Title Regulations can lift the lowest-rated opponents for the norm calculation, which helps in exactly this situation; ask the chief arbiter how they apply in your event.

Step 4: the composition rules

A 2450 performance is necessary, not sufficient. For an IM norm, at least a third of the opponents, and at least three of them, must hold the IM or GM title; at least half must hold FIDE titles of any kind; and opponents must come from several federations, with limits on how many can be from the player's own. In our example, a player who has met three IMs and a GM is on track; one who has played only untitled compatriots is not, however good the score. Organisers of norm events plan the field so that players near the top will meet enough titled and foreign opponents, and they often publish norm chances before the last rounds.

Common mistakes

• Counting only the games played so far. The norm is judged on all the games, with the full average.
• Forgetting the rounding. 2449.5 rounds up to 2450, which can save half a point.
• Ignoring the 35% minimum. Rarely a problem for a norm, but it exists.
• Assuming any 2450 performance is a norm. Titled and foreign opponent requirements must also be met.
• Playing for a draw too early. If the average drops in the last round, a draw may no longer be enough.

Norm checklist

1. Calculate the average opponent rating so far and estimate the remaining opponents.
2. Use the norm calculator for the score needed over all games.
3. Recalculate after every round as the pairings become known.
4. Count titled opponents, GMs and IMs, and foreign federations.
5. Ask the chief arbiter about rating floors and whether the event is registered for norms.
6. After the event, make sure the arbiter submits the norm certificate.