USTA Levels (NTRP) Guide
PTA Tips for Rankings:
1) The Descriptions above for NTRP are very vague and can be misleading to some people. Many will often over-rate themselves because of this. They kind of have to be taken in a 'compared to a pro player' mentality.
2) The Guidlines table at above link may give some idea as to actual levels for college kids, top high schoolers, etc for you to compare. For example, a 26 year old former Division II or III college player is at minimum a 4.5 level.
3) The bell curve for tennis players at recreational level is about 3.5 to 4.0, many who have been playing for years or decades. Odds are many of the experienced people you see at the park are at this level
4) At a park, ask a seemingly experienced player to help you by letting you know their ranking level. This will help you gauge abilities that you see on the court against different levels.
5) Doubles are often put together in a combination. We follow this also. So 6.0 doubles means that the sum of the partners levels should be 6.0 or less.