The edge is an interval, not a number

Every betting screen prints one figure to two decimal places. That figure is a modelling choice wearing a measurement's clothes. Bookbreaker reports the range, the chance you can actually get the bet down, and what your own record can and cannot support.

Two numbers no competing screen prints: the band the four devig methods allow, and the chance the price is still there when you tap it.

Same market, four defensible methods

Removing a book's margin to recover what it really believes is a modelling choice, not arithmetic. On a -145 / +125 moneyline the four standard methods disagree by 0.39 points of probability:

Consensus 57.34%. On a market where a 2% edge is a good day, that spread is a quarter of the edge. Every competing tool picks one of those rows, hard-codes it, and prints the result as fact.

A stake a person would actually place

At +110 and +105 there is a 3.73% arbitrage. Every calculator hands you this:

493.98 and 506.02 → 37.35 guaranteed

A precise stake to the cent is the most-cited fingerprint risk desks use to identify arbitrage. Bookbreaker solves for round stakes directly:

490 and 500 → 35.00 guaranteed

The 2.35 difference is named and reported, not hidden. A tool that conceals its own trade-offs is not one you can check.

An edge you cannot take is worth nothing

Quote age is measured from the book's own timestamp, not from when the feed reached us. On a feed running 5.4 seconds behind, a quote that looks 10 seconds old is really 15.4:

still available: 84% — a screen ignoring latency would say 89%

What your record actually says

On a 220-bet history showing +1,300 profit and 5.91% return, Bookbreaker's verdict is:

+5.91% flat-bet ROI, but the interval spans zero (-7.0% to +18.9%) — indistinguishable from break-even

Every other tracker prints 5.91% and stops.