Data sources and licences
The data behind Kelly's numbers, what each source is used for, and the credit each licence asks for.
Updated November 6, 2026
How Kelly uses outside data
Kelly uses its own accounts and licences with every data source, and reads each one's terms before its data reaches a page. A source whose terms are not yet confirmed stays internal.
Per-book prices show only on askkelly.ai. The API, MCP and other sites get values Kelly computes from them: the consensus, the hold, the break-even and the move.
Each source below is credited here as its licence asks.
Sources (11)
| Source | Used for | Credit |
|---|---|---|
| The Odds API | Sportsbook odds and line moves across sports | Odds data via The Odds API |
| nflverse | NFL schedules, rosters, injuries, player stats and published closing lines | nflverse data (CC BY 4.0) |
| BALLDONTLIE | NBA, WNBA, college basketball and NFL games and stats | No credit required |
| CollegeFootballData | College football games, stats and TV listings | Data provided by CollegeFootballData.com |
| CollegeBasketballData | College basketball games and stats | Data provided by CollegeBasketballData.com |
| Retrosheet | MLB game logs and game information | The information used here was obtained free of charge from and is copyrighted by Retrosheet. Interested parties may contact Retrosheet at "www.retrosheet.org". |
| SABR Lahman Baseball Database | MLB season history | SABR Lahman Baseball Database, licensed under CC BY-SA 3.0 |
| Chadwick Baseball Bureau Register | Baseball people and player IDs | Chadwick Baseball Bureau Register, available under the Open Data Commons Attribution License (ODC-BY 1.0) |
| Cricsheet | Cricket ball-by-ball match data | Contains information from Cricsheet (cricsheet.org), made available under the ODC Attribution License |
| Squiggle | AFL fixtures, results and ladder | AFL fixtures, results, ladder and model tips: Squiggle (squiggle.com.au) |
| National Weather Service | Game-day weather forecasts | Forecast: National Weather Service |
Showing (11) of (11) sources whose data appears on the site, each with the credit its licence asks for.