Iva Jović @ Jessica Pegula
| Side | Market | Best Line | Worst |
|---|---|---|---|
| home | h2h | DraftKings: +194 | +180 |
| away | h2h | Bovada: -230 | -260 |
| home | spreads | Bovada: -105 (+3.5) | -107 |
| away | spreads | Bally Bet: -122 (-3.5) | -125 |
| over | totals | Bally Bet: -113 (+21.5) | -113 |
| under | totals | Bally Bet: -115 (+21.5) | -115 |
Yuliia Starodubtseva @ Madison Keys
| Side | Market | Best Line | Worst |
|---|---|---|---|
| home | h2h | Bally Bet: -420 | -525 |
| away | h2h | DraftKings: +362 | +300 |
| home | spreads | Bally Bet: -137 (-4.5) | -137 |
| away | spreads | Bally Bet: +106 (+4.5) | +106 |
| over | totals | Bally Bet: -103 (+20.5) | -103 |
| under | totals | Bally Bet: -129 (+20.5) | -129 |
Frequently Asked Questions
What are the best WTA Charleston Open lines today?
The table below shows which sportsbook has the best available price on each side of every upcoming WTA Charleston Open event. Line shopping across multiple books can save you 1–3% per bet compared to sticking with a single sportsbook.
What is vig (vigorish) in sports betting?
Vig — short for vigorish, also called juice or overround — is the margin a sportsbook builds into its odds. It's the difference between the true probability of an outcome and what the odds imply. Lower vig means you keep more of your winnings on every bet. For example, a standard -110/-110 line has about 4.76% vig.
How often is this data updated?
We pull fresh odds from The Odds API three times per day — at 6:00 AM, 2:00 PM, and 10:00 PM UTC. Each snapshot captures the latest lines from every sportsbook that has posted odds. The timestamp at the top of the page shows the most recent refresh.
How is the vig grade calculated?
Each sportsbook is graded on a letter scale based on average vig: A+ (under 2%) is exceptional, A (2–3%) is excellent, B+ (3–4%) is above average, B (4–5%) is the industry standard, C (5–6%) is below average, and D (above 6%) indicates high-juice markets.
Why does lower vig matter for bettors?
Lower vig directly impacts your long-term returns. A bettor placing $1,000 per week at a book with 4% vig loses roughly $40/week to the house edge. At 2% vig, that drops to $20/week — a $1,040 difference over a year. For serious bettors, shopping for lower vig is one of the most reliable ways to improve profitability.
What sportsbooks do you track?
We track both regulated US sportsbooks (DraftKings, FanDuel, BetMGM, Caesars) and offshore books (Bovada, BetOnline, MyBookie, BetUS, LowVig.ag, BetAnySports). Data comes from The Odds API, which aggregates real-time lines from licensed sources.
How We Calculate These Numbers
- Data Source
- All odds on this page come from The Odds API, which aggregates real-time lines from licensed US and offshore sportsbooks. We track moneyline, spread, and totals markets across every sport with active betting lines.
- Update Frequency
- We pull a fresh snapshot of every tracked market three times per day — at 6:00 AM, 2:00 PM, and 10:00 PM UTC. Each snapshot captures the latest lines from every sportsbook that has posted odds for a given event. The timestamp at the top of each page tells you exactly when the data was last refreshed.
- Vig Calculation
- Vig (short for vigorish, also called juice or overround) measures the margin a sportsbook builds into its odds. We calculate it by converting the odds on each side of a market to implied probabilities, summing those probabilities, and subtracting 100%. For example, a market priced at -110/-110 implies 52.38% on each side — a total of 104.76%, meaning a vig of 4.76%. Lower vig means better value for bettors because you keep more of your winnings.
- Per-Market Breakdown
- We compute vig separately for each market type: moneyline (h2h), point spreads, and totals (over/under). The "average vig" shown for each sportsbook is the mean across all market types weighted by the number of events sampled in each market.
- Grading Scale
- Every sportsbook receives a letter grade based on its average vig: A+ (under 2%) is exchange-level pricing. A (2–3%) is very competitive. B+ (3–4%) is above average. B (4–5%) is the industry standard — a -110/-110 line is 4.76%. C+ (5–6%) is slightly below average. C (6–7%) is below average. D (7–8%) is high vig. D− (8–10%) is very high vig. F (10%+) is predatory pricing. See the full Vig Index Methodology for formulas, worked examples, and known limitations.
- Trend Tracking
- We store daily snapshots for 30 days, allowing us to show 24-hour and 7-day vig trends. A downward trend (improving) means sportsbooks are tightening their lines — often in response to increased competition or higher betting volume as a season heats up.