Better price
An edge is a price that pays more than BeatVig's fair-price estimate for the same bet, after the sportsbook's margin (the vig) has been removed. A bigger edge means the price is further from fair — not a bigger chance the bet wins.
Sports betting terms, in plain English
What the words on BeatVig's boards actually mean — with one of our own live numbers below.
Typical sportsbook vig right now
6.97%
Right now, across 30577 live two-sided quotes BeatVig prices, the typical sportsbook charges 6.97% vig and the typical prediction-market spread is 3.53%.
In short
This page defines the terms used across BeatVig's boards — vig, fair price, de-vigging, arbitrage, hold, implied probability and more — each tied back to how BeatVig actually prices a bet. Right now, across 30577 live two-sided quotes BeatVig prices, the typical sportsbook charges 6.97% vig and the typical prediction-market spread is 3.53%.
Fair price
The fair price is what a bet would cost with the sportsbook's own built-in margin (the vig) mathematically removed, so the two sides of the bet add up to exactly 100% instead of more. BeatVig computes it from a sharp venue's own two-sided price and calls the process "de-vigging" — every price on the site is compared against this number, never against a guess.
Vig
Vig (short for "vigorish") is the margin a sportsbook builds into a two-sided price, measured as how far the two sides' implied probabilities add up past 100%. A -110/-110 market implies 52.38% on each side, which totals 104.76% — the 4.76% over 100% is the vig, paid whether the bet wins or loses.
After the fee
"After the fee" (or "net of fee") means a prediction-market price with that venue's own trading fee already subtracted, so it can be compared fairly against a sportsbook price, which carries its margin built in rather than charged separately. When a venue charges no fee on a given bet, BeatVig says so directly instead of implying a deduction that never happened.
De-vigging method
A de-vigging method is the formula used to strip a sportsbook's margin back out of a two-sided price. BeatVig's default is multiplicative (dividing each side's implied probability by the pair's total); additive, power and shin are alternative formulas that split the margin differently, and can produce a slightly different fair price on the same market.
Arbitrage
Arbitrage betting means buying both sides of the same bet at two different venues whose combined price is under 100%, so either outcome pays back more than the total staked — as long as both bets stand at the prices taken. A venue can limit, void, or reprice a bet before both legs settle, so this depends on both legs actually holding.
Hold
Hold is another name for vig or juice: the margin a sportsbook keeps built into its prices regardless of outcome. BeatVig's Vig by Book page measures the live median hold at every sportsbook it tracks.
Prediction market
A prediction market — Kalshi, Polymarket, Novig or ProphetX — is an exchange where traders buy and sell yes/no contracts on an outcome, so the contract's own price is the market's probability estimate. The venue charges its own trading fee separately, instead of folding a margin into the quote the way a sportsbook does.
Line
A line is the number a bet is set against — a point spread, a game total, or a player-prop threshold like "23.5 points." It's distinct from the price (the odds) attached to either side of that line, which is what changes as a market moves even when the line itself doesn't.
Juice
Juice is the common sportsbook-slang name for vig: the margin a sportsbook builds into a two-sided price. Laying -110 to win $100 on a true coin-flip bet, instead of even money, is the juice — both -110 sides imply 52.38%, which adds up to 104.76%, or 4.76% of juice.
Steam
Steam is a fast, same-direction price move that shows up across several venues at once, typically following a bet (or a cluster of bets) that other books and exchanges follow by moving their own number. BeatVig's line-movement pages chart how a price has moved since it opened.
Hit rate
Hit rate is how often a player's actual stat has cleared a given line over their recent games — for example, "8 of the last 10 games over 23.5 points" is an 80% hit rate. It describes the past, not a probability of the bet winning tonight.
Beating the close
Closing line value (CLV) is the gap between the price you got on a bet and where that same market closed just before the event started. Consistently beating the close, across many bets, is one of the strongest signs that a bettor has a real, repeatable edge — independent of whether any single bet actually won.
Glossary — FAQ
What is better price?
A price that pays more than the fair price for the same bet, once BeatVig has removed the vig.
What is fair price?
The price a bet would carry with no venue margin built in — what BeatVig calls "de-vigged."
What is vig?
The cut a sportsbook builds into a two-sided price — how far both sides' implied probabilities add up past 100%.
What is after the fee?
The number after subtracting what the exchange charges to trade — not what a sportsbook charges, which is already built into its price.
What is de-vigging method?
How BeatVig splits the vig back out — multiplicative, additive, power or shin — to get the fair price.