UKD Calculation: How Turkey's National Chess Rating Works

UKD (Ulusal Kuvvet Derecesi) is the national chess rating calculated by the Turkish Chess Federation (TSF) and used in tournaments in Türkiye. It works much like the FIDE Elo rating but follows its own procedure (TSF-TK-PRS/05 and its 2011 revision). This article explains the formula, the coefficients and a worked example, and points you to a tool that does the maths automatically.

The formula

New UKD = old UKD + ΔD, where ΔD = K × (W − We). W is the score you made in the event and We is the score expected from you given your opponents' ratings. The expected score is looked up game by game from the same expectancy table FIDE uses, and the values are added up.

K-factor

2400 and above: K = 10
2000–2399: K = 15
1600–1999: K = 20
1300–1599: K = 25
1299 and below: K = 30

Special rules

350-point cap: a rating difference above 350 counts as 350.
Against an unrated opponent (or one rated below 1000): a win gives +K/10, a loss −K/10, a draw nothing.
Floor: UKD never drops below 1000.
Winner rule: the individual winner of the event cannot lose UKD points.
Only classical events (at least 60 minutes per player) count; rapid and blitz have separate lists.
An unrated player receives a performance rating for the event if they faced at least three rated opponents.

Worked example

A player rated 1451 (K = 25) plays six rounds: wins against 1126, 1288, 1361 and 1177, loses to 1538 and draws with 1240. The expected scores are 0.87, 0.72, 0.62, 0.83, 0.38 and 0.77, a total of 4.19. The actual score is 4.5, so the change is 25 × (4.5 − 4.19) = +7.75 and the new rating is 1459, exactly what the federation published.

Automatic calculator

Paste your chess-results link into the mytourneys Elo/UKD calculator: opponents, results and ratings are read automatically and your UKD and FIDE Elo change is shown round by round, together with win/draw/loss scenarios for the next round. The calculation was verified against the federation's official rating report for 559 out of 559 games. Manual entry is available for events that are not on chess-results.

💡 The fastest way to raise your UKD is to play stronger opponents: thanks to the 350-point cap, losing to a much stronger player costs little, while beating one earns a lot.