UDisc to PDGA Rating Converter

Two scales, no official bridge

A PDGA round rating lands on the familiar 1000-point scale, where 1000 is a scratch round and roughly ten points is one throw. A UDisc round rating lands on a 1-300 scale. They measure a similar thing - how well you played relative to the difficulty of the layout - but they are computed by different organisations from different data, and UDisc deliberately does not publish a conversion between them.

That is a defensible decision on their part. Publishing a mapping would imply the two numbers are interchangeable, and they are not: the PDGA establishes a layout's scratch scoring average from a field of known-rating players at a sanctioned event, while UDisc derives difficulty from its own scoring data across courses that have mostly never hosted one. The inputs differ, so the outputs cannot be made to agree exactly.

It does leave a practical gap, though. If your league runs on UDisc and your rating lives on the 1-300 scale, you still need a way to talk about it with players who think in 1000-scale terms.

How this converter works

We use a linear fit against rating pairs that players report for the same round - a round that UDisc rated and that also has a PDGA round rating:

PDGA scale = 2 x UDisc rating + 500

A straight line is the honest choice here. Across the range players actually shoot, the two scales track each other proportionally, and the data behind the fit - self-reported pairs, not a published mapping - is nowhere near precise enough to justify a curve. A more elaborate formula would look more authoritative while being no more correct.

The two coefficients are isolated in a single config constant so they can be re-fitted later. Once enough DiscNest users have entered rounds from both sources, our own paired data will beat a community rule of thumb, and the fit gets updated in one place.

What it can and cannot tell you

Read the output as a ballpark within about a rating class, not as a figure to quote. It is good enough to answer "roughly where do I sit on the scale my club talks in?" It is not good enough to settle an argument about whether someone is a 935 or a 950 player, and it is not a PDGA rating - only sanctioned play produces one of those.

This is why DiscNest marks every UDisc-sourced round as estimated wherever it appears. If you have a PDGA round rating for a round, enter that instead: it is exact, and mixing exact rounds with estimated ones quietly degrades everything computed from them.

Finding your UDisc round rating

UDisc Pro shows a round rating on scored rounds played on a Smart Layout with a difficulty classification. Open the round in your UDisc history and the rating sits with the scorecard. Rounds on layouts without a difficulty classification are not rated at all - there is no number to convert, and you are better off entering your score with the layout's scratch scoring average instead.

Frequently asked questions

Can you convert a UDisc rating to a PDGA rating?

Approximately, yes. UDisc round ratings sit on a 1-300 scale and PDGA round ratings sit on a 1000-point scale, but UDisc does not publish an official mapping between them. Any converter, including this one, is an unofficial estimate fitted to rating pairs players report for the same round.

What is the formula?

We use a linear fit: PDGA scale = 2 x UDisc rating + 500. It is a straight line because the two scales behave proportionally across the range players actually shoot, and because a more elaborate curve would imply a precision the underlying data does not support.

How accurate is it?

Treat it as a ballpark within roughly a rating class, not an exact figure. The conversion is fitted to community-reported pairs rather than to a published mapping, and UDisc computes its ratings from its own course difficulty model. If you have a PDGA round rating for the same round, that number is exact and this one is not.

Where do I find my UDisc round rating?

UDisc Pro shows a round rating on scored rounds played on a Smart Layout that has a difficulty classification. Open the round in your UDisc history and the rating appears with the scorecard. Rounds on layouts without a difficulty classification are not rated at all.

Why does UDisc use a different scale from the PDGA?

They are separate systems built for separate purposes. PDGA round ratings come out of sanctioned play, where a field of known-rating players establishes the scratch scoring average for the layout. UDisc rates rounds from its own data across every course in its database, including the great majority that have never hosted a sanctioned event, so it built its own scale rather than borrowing one that assumes a rated field.