Glossary / Betting math / No-vig CLV
A ParlayAPI glossary entry

No-vig CLV

No-vig CLV is closing line value graded against the sharp book's devigged closing probability instead of the raw (vigged) closing price. It is the professional grading convention, because comparing your entry price to a vigged close double-counts the bookmaker's margin.

Worked example

# You bet Team A at +105 on Tuesday
        your implied price          = 100 / 205          = 48.8%
        close (sharp book)          = -110 / -110
        devigged closing prob       = 52.38% / 104.76%   = 50.0%
        
        # No-vig CLV: you beat the fair close by 1.2 points of probability.
        # Grading against the vigged -110 close (52.4%) would overstate
        # your edge by the size of the vig.

Over a large sample, positive no-vig CLV is the cleanest public evidence that a betting process finds real value rather than noise.

Where it shows up in ParlayAPI

ParlayAPI archives 1.7M+ historical game closing lines (continuous depth back to 2005, as of 2026-08) and 30M+ player-prop closing lines (since June 2022), served from /v1/historical/sports/{sport_key}/odds. Pull the close, devig it, and grade your entries. The full method: no-vig CLV explained.

Related terms

Closing Line Value (CLV)The gap between your price and the close. Closing lineThe market's final pre-game price. DeviggingStrip the bookmaker margin to a fair probability. No-vig priceA price with the book's margin stripped out.