tag — fundamentals
fundamentals
Every OddsRelay post tagged fundamentals.
19 notes
- Exchange & lay data
Back and lay odds, explained for builders
Backing bets for an outcome; laying bets against it, and only an exchange lets you take that side. Here is the plain version, plus the back/lay data pair a matched feed hands you ready to use.
· 5 min read
- Fundamentals
Bookmaker margin and the overround, explained
The overround, the margin, the vig: three names for the bookmaker's built-in edge. Here's how to compute it from decimal prices, and why comparing it across books tells you who to bet with.
· 5 min read
- Fundamentals
Decimal and fractional odds in data: what to standardise on
Decimal, fractional and American are three ways to write the same price. For anything you compute with, standardise on decimal, store decimal, and convert only at the point of display.
· 4 min read
- Fundamentals
How bookmaker odds data is structured
Odds data is a four-level hierarchy: event to market to selection to price, plus bookmaker, region and freshness metadata. Once the shape clicks, integrating a feed is straightforward.
· 5 min read
- Fundamentals
How odds feeds handle suspended and void markets
Markets get suspended or voided constantly, and a feed that hides those states will hand your users a wrong price. Here is how a good feed represents them, and what your product should do with each.
· 6 min read
- Fundamentals
How to monitor an odds feed in production
Once an odds feed is live, three checks keep you honest: availability, freshness against the timestamp, and coverage of your books and markets. Here is how to build them so you catch a problem before your users do.
· 7 min read
- Fundamentals
How to price a bet with odds data
Pricing a bet is four steps: implied probability, remove the overround, derive a fair price, then compare across books. Sharp books and exchanges give the best estimate of the true probability.
· 6 min read
- Fundamentals
How to store and version odds data
A feed gives you current prices; the history is what you persist from them. Here's a simple, durable model: timestamped snapshots keyed by event, market and selection, plus the retention trade-offs to decide up front.
· 6 min read
- Fundamentals
Integrating an odds feed with AI coding tools
Point an AI coding assistant at a public OpenAPI spec, describe what you want, and get a working odds-feed call to iterate on. Here's why a clean contract makes that work, and how to do it safely.
· 5 min read
- Fundamentals
Line movement: what odds data shows you
Line movement is how a selection's odds shift as money comes in and information arrives. This is how odds data represents that movement, and what you can honestly read from it.
· 6 min read
- Fundamentals
Live vs pre-match odds data: what's realistic
Live in-play and pre-match odds data are different problems with different costs. Here's how to tell which one your product actually needs before you shop, and why we ship pre-match and say so.
· 6 min read
- Fundamentals
Multi-sport odds data: football, racing, tennis and beyond
A full odds-data layer runs well past football and racing into tennis, cricket, rugby and basketball. Here is what multi-sport coverage really means, and why depth per sport beats a long list that thins out.
· 6 min read
- Fundamentals
Odds API vs odds feed: what's the difference?
Builders hit two terms for the same data and assume they're choosing between products. They aren't. Here's what each word stresses, and the distinction that actually changes your build: raw versus matched.
· 5 min read
- Fundamentals
Odds API vs sports data API: what's the difference?
A sports data API delivers scores, fixtures and player stats. An odds API delivers bookmakers' prices for outcomes. They're different products, they're often used together, and only one is what matched betting runs on.
· 5 min read
- Matched betting & oddsmatcher
Qualifying loss and matched-bet ratings, explained
Two fields decide whether a matched bet is worth placing: the rating and the qualifying loss. Here is what each one means, conceptually and honestly, and how a matched feed computes them for you.
· 5 min read
- Arbitrage & value betting
Value betting vs arbitrage: a data view
Arbitrage and value betting look similar from the outside and differ sharply underneath. Here is the comparison from a data angle: different risk profiles, different data needs, one feed that serves both.
· 5 min read
- Fundamentals
Webhooks vs polling for odds data
Odds change continuously, not at discrete events, so polling with ETag/304 fits the data better than webhooks. Here's the plain comparison, and why OddsRelay is pull-based.
· 5 min read
- Exchange & lay data
What is a betting exchange? A data primer
A betting exchange lets bettors bet against each other, backing or laying, with the exchange taking commission. Its lay prices are the other half of every matched and arbitrage pair.
· 5 min read
- FundamentalsGuide
What is an odds API? A 2026 guide for builders
An odds API hands your software bookmakers' prices as structured data instead of a human reading betting sites by hand. Here's what one returns, how raw and matched feeds differ, and what to check before you commit.
· 6 min read
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