Initial DWZ, unaffiliated players and foreign ratings
Who gets a first DWZ and how it's calculated (WO 3.4), why unaffiliated players don't receive a DWZ (WO 3.4.3), and when FIDE Elo counts as a foreign/converted rating (WO 4.1.2).
Who gets an initial DWZ? (WO 3.4.1)
Players who have neither a DWZ nor a usable foreign/converted rating before the tournament ends receive an initial DWZ R1.
- Stage 1: at least 5 opponents with a DWZ, scoring at least 0.5 points among them — carry-over games from earlier tournaments count too.
- Stage 2: at least 5 games against opponents who are also just receiving their initial DWZ (joint iteration).
If there aren't enough games, they are stored as carry-over games and combined with later tournaments (WO 3.4.2). They expire after two years (WO 4.1.1).
How is it calculated? (WO 3.4.4, Appendix 1.2.2)
The starting point is the opponent average Rc plus D(p), where p is the score share. It is then iterated until points and expectation match (Ri). At 100%, a hypothetical draw against Rc is added.
A correction then pulls young ratings toward the middle: R1 = Ri if Ri ≥ 2000; R1 = Ri + 0.08 · (2000 − Ri) if 1100 ≤ Ri < 2000; R1 = 1100 + 9 · 0.08 · Ri / 11 if Ri ≤ 1100. A negative Ri is set to 0; the lowest possible initial DWZ is 1100.
The corrected R1 then also counts as the opponent rating for the tournament's established players (WO 3.4.4.2) — which is why games against "unrated" players count in the forecast as soon as they reach an initial DWZ.
Unaffiliated players (WO 3.4.3)
Unaffiliated players are included in the calculations — they count normally for their opponents — but neither a DWZ nor carry-over games are published or stored for them.
If an unaffiliated player later joins a club, tournaments can be rated retroactively within a year. The calculator therefore shows an initial DWZ estimate as "conditional": it states what the number would be, not that it will actually be issued.
Foreign/converted rating: FIDE Elo instead of DWZ (WO 3.4.1, 4.1.2)
For players without a DWZ — especially players from abroad — FIDE ratings (and, failing that, other national ratings) should be used, provided the rating office has classified them as comparable. In the WO's own example (Appendix 3.1), the Elo rating is carried over 1:1.
A player with a usable foreign/converted rating does not get an initial DWZ from the tournament; the foreign/converted rating becomes their R0. The calculator marks such opponents as "foreign/converted rating".
Whether a foreign/converted rating is recognised in an individual case is decided by the rating office — the calculator can only assume it.
Frequently asked questions
I played five games, why doesn't the calculator show an initial DWZ?
Only games against opponents with a DWZ count (stage 1), and at least half a point must be scored among them (WO 3.4.1.1). Forfeit games don't count.
For an unaffiliated player with an Elo rating, does the Elo or an initial DWZ count?
The Elo rating counts as a foreign/converted rating — it rules out the initial DWZ (WO 3.4.1). Unaffiliated players don't receive a DWZ anyway (WO 3.4.3).
Why can my initial DWZ differ from the calculator's estimate?
The calculator doesn't know your carry-over games from earlier tournaments (WO 3.4.2). The rating office includes them.
Source: DSB rating regulations, valid from 8 June 2026. Last updated: 14/09/2026. Unofficial explanation, not legal advice.