The CS2 data & odds glossary
Plain-English definitions of the terms you meet in CS2 and esports data — ADR, KAST, entry frags, eco rounds, the map veto, implied probability, and more.
- cs2Jul 21, 20262 min read
Overround, defined
The overround is the total of a market's implied probabilities — 104.76% on a standard two-way market. The amount above 100% is the margin.
Read it → - cs2Jul 21, 20262 min read
No-vig odds, defined
No-vig odds are a market's prices with the margin removed, so the implied probabilities sum to exactly 100% instead of more. Also called fair odds.
- cs2Jul 21, 20262 min read
Fair value odds, defined
Fair value odds are the price an outcome would carry if it were priced at its true probability with no margin — the break-even price, not a recommendation.
- cs2Jul 21, 20262 min read
Decimal odds to implied probability
To convert decimal odds to an implied probability, divide 1 by the price. Decimal 2.50 implies 40%. The conversion is arithmetic, not opinion.
- cs2Jul 21, 20262 min read
American odds to decimal odds
Convert American odds to decimal: positive prices are (odds ÷ 100) + 1, negative prices are (100 ÷ |odds|) + 1. So -110 becomes 1.91 and +150 becomes 2.50.
- cs2Jul 10, 20261 min read
VRS: Valve Regional Standings, defined
VRS, the Valve Regional Standings, is the official CS2 points system that decides Major invites — built from prize money and results, not an ELO rating.
- cs2Jul 10, 20262 min read
Vig (overround), defined
The vig, or overround, is the margin built into betting odds — the reason a market's implied probabilities add up to more than 100% instead of a true 100%.
- cs2Jul 10, 20262 min read
Trade kill in CS2, defined
A trade kill is killing the opponent who just killed your teammate, within a short window — turning a lost CS2 entry duel into an even exchange of players.
- cs2Jul 10, 20262 min read
Market line, defined
The market line is a single fair-odds probability derived from multiple bookmakers and exchanges, with the margin removed and no individual source named.
- cs2Jul 10, 20262 min read
Map veto in CS2, defined
The map veto is the alternating ban-and-pick sequence before a CS2 series that decides which maps are played — a public read on each team's preparation.
- cs2Jul 10, 20262 min read
KAST in CS2, defined
KAST is the share of CS2 rounds where a player gets a kill or assist, survives, or is traded — a consistency measure whose professional median sits near 72%.
- cs2Jul 10, 20262 min read
Implied probability, defined
Implied probability converts decimal odds into a percentage chance: it is simply 1 divided by the price, and across a market the total always tops 100%.
- cs2Jul 10, 20262 min read
HLTV Rating, defined
HLTV Rating is the composite CS2 player rating where 1.00 marks an average professional game, rolling kills, damage, survival and consistency into one number.
- cs2Jul 10, 20262 min read
Head-to-head (H2H) in CS2, defined
Head-to-head (H2H) in CS2 is the prior meeting record between two teams. Useful context, but a small, often stale sample — and how to pull it from the API.
- cs2Jul 10, 20262 min read
Force buy in CS2, defined
A force buy in CS2 is spending everything on a round you can't properly afford, usually to deny an opponent's economy. The risk, and what the data shows.
- cs2Jul 10, 20262 min read
Entry frag in CS2, defined
The entry frag is the first kill of a CS2 round — the opening duel. Why it's the highest-leverage moment, how it's measured, and why K/D undervalues it.
- cs2Jul 10, 20262 min read
Eco round in CS2, defined
An eco round in CS2 is a deliberate save: a team buys almost nothing to afford a full buy next round. Why a disciplined full save beats a half-committed buy.
- cs2Jul 10, 20262 min read
De-vigging, defined
De-vigging removes the margin from odds, rescaling the implied probabilities back to 100% to recover the market's fair, comparable probability estimate.
- cs2Jul 10, 20262 min read
Clutch (1vN) in CS2, defined
A clutch in CS2 is a round won by the last player alive against one or more opponents (1vN). Why raw clutch counts mislead, and how to measure conversion.
- cs2Jul 10, 20262 min read
Bo3 (best of three) in CS2, defined
A Bo3 (best-of-three) is a CS2 series where the first team to win two maps takes the match — the standard playoff format, and why it interacts with the veto.
- cs2Jul 10, 20262 min read
ADR in CS2: average damage per round, defined
ADR in CS2 is average damage per round, the cleanest single measure of a player's output. What counts as a good ADR, how it's measured, and what it misses.