The difference in one sentence
Bet365 gives you a fixed decimal price for a selection. Betfair Exchange gives you a back and lay order book, including the price and displayed size available at each level.
A higher displayed Exchange back price can narrow after commission or disappear before an order is filled. This pilot found one event with close enough source times for a direct example. It does not establish which source generally has better odds.
One matched NFL example
We read Chicago Bears vs Philadelphia Eagles at , before its scheduled start. Both rows described the same two-way, full-time moneyline selections. Bet365's source quote was 240 seconds old; Betfair's was 272 seconds old. Their source timestamps were 32.2 seconds apart.
| Selection | Bet365 fixed odds | Betfair best back | Displayed back size* | Back odds after illustrative 2% commission† |
|---|---|---|---|---|
| Chicago Bears | 2.70 | 2.88 | 480.28 | 2.8424 |
| Philadelphia Eagles | 1.49 | 1.52 | 124.55 | 1.5096 |
*The odds snapshot did not label the size currency. Displayed size is not a guaranteed fill. †The final column models one isolated winning back bet; it is not an account quote or a universal Betfair rate.
Why the API rows look different
- Bet365 sportsbook
- One fixed-odds selection row with event, market, period, side and decimal price. Use the current bookmaker key returned by
GET /v1/bookmakersfor your account and region; this capture returnedbet365. - Betfair Exchange projection
- The regular odds snapshot can contain a
betfairrow markedsource_type=exchange_bookmaker_projection. Its best back price and size allow a basic side-by-side view, but they do not show the whole ladder. - Betfair Exchange order book
- The dedicated exchange endpoint returns available-to-back and available-to-lay levels, size, and other exchange fields where supplied. Best lay is a different offer from best back; last traded price describes a past match, not the current best offer.
Betfair Exchange and Betfair Sportsbook are separate products. This page compares the Exchange market-data feed with Bet365 sportsbook odds. Betfair's own API guidance makes that distinction.
A price comparison needs size and commission
For one isolated winning back bet, the illustrative calculation is 1 + (back odds − 1) × (1 − commission rate). At 2%, a displayed 2.88 becomes 2.8424 in this scenario. Betfair says Exchange commission is charged on net market winnings; the applicable rate depends on the customer and market. Multiple positions in one market need a market-level profit-and-loss calculation.
The best back price applies only to the size displayed at that level. Larger orders can use worse ladder levels, and the offer can change. Use the exchange order-book API to inspect depth before modelling a target stake. Betfair's market-data documentation describes best offers, available size and traded prices.
What was matched, and what was left out
Between and , a read-only script paged upcoming events in soccer, basketball, baseball and American football, then requested the public V1 odds snapshot for events listing both sources. It compared event ID, market, period, line and selection side, and kept only available full-time moneyline rows.
- 404upcoming event records scanned
- 17listed both source keys in event metadata
- 7returned snapshot rows for both
- 6had at least one exactly matched available moneyline selection (13 selection pairs)
- 1had both source quotes at most five minutes old and source times at most one minute apart
Listing both keys did not mean both current prices were returned. The scan covered four sports and at most ten cursor pages per sport. One short window and one fresh event are too little evidence for a general price ranking, a coverage rate or a fill-rate claim. We did not place a bet or read the odds history store.
Download the credential-free pilot data (JSON). The file includes the collection window, counts, freshness rule and selected price rows.
Reproduce the comparison in your application
Get the event and current bookmaker keys first. For the pilot event, the regular snapshot supplied the paired Bet365 and Betfair projection rows:
GET /v1/events/599470/odds/snapshot?bookmakers=bet365,betfairFor Betfair's back and lay ladder, call the separate endpoint:
GET /v1/events/599470/exchange/orderbook/snapshot?exchanges=betfair&depth=3Match selection identity and source times before comparing prices. Keep quote age, size and your actual commission calculation alongside the result. odds-api.net currently provides pre-match data and does not place Bet365 or Betfair bets.
Questions about this comparison
Is Betfair Exchange always a better price than Bet365?
No general winner follows from one event. Compare the same pre-match event, market, period, line and selection at close source times, then account for available size and your actual commission.
Is Betfair Exchange the same as Betfair Sportsbook?
No. Betfair Exchange exposes back and lay offers from an order book. Betfair Sportsbook is a separate fixed-odds product. This comparison uses Betfair Exchange.
Does odds-api.net place bets or provide in-play odds?
No. odds-api.net provides pre-match market data and supported pre-match streaming updates. It does not place Bet365 or Betfair bets or manage their customer accounts.