What does the Closing line value calculator show?

It compares the inverse probabilities of an entered bet price and closing price.

Should I treat the result as a forecast?

No. It is a calculation based on the values entered. Market rules, settlement and price movement can change how a real bet is settled.

Closing Line Value Calculator for Price Comparison

Last updated: 22 August 2026 Written by Ellie Marsden, Senior Betting Editor Fact checked by Tom Brackley, Odds Analyst

What this calculator answers

Compare the decimal price taken with a later closing decimal price. The calculator expresses the change as a percentage based on inverse price and shows both implied probabilities.

Formula and worked example

Formula: CLV percent = (closing implied probability divided by bet implied probability minus 1) multiplied by 100. Implied probability = 1 divided by decimal odds.

A bet at 2.50 has implied probability 40 percent. A close at 2.20 has implied probability 45.45 percent. CLV is (45.45 divided by 40 minus 1) times 100, or 13.64 percent.

Checks before using the result

Comparing prices from different market definitions.
Using a closing price recorded after settlement.
Treating one comparison as evidence of a repeatable edge.

When the calculation does not apply

It compares two entered prices only. It does not account for margin changes, liquidity, different settlement terms or whether either price was actually available.

Keep the number in context

A calculator makes the arithmetic visible, but it does not decide whether a price fits your budget or information. Write down the stake before placing anything, check the market rules, and keep essential money separate. The result is a planning figure, not a prediction of what will happen.

For another view, visit the calculator hub, compare the Parlay odds and Break even win rate, or read the odds format guide. These tools use the same price conventions, so you can check a number from more than one angle.

Reading a rounded result

Displayed money amounts are rounded to two decimal places, while a real settlement can apply its own rounding sequence. Keep the original inputs beside the result if you need to repeat the calculation later.

If an input is unclear, pause and find the stated market term rather than guessing. A useful check is to change one input by a small amount and see whether the result moves in the direction you expect.

That does not validate the market, but it can reveal a reversed sign, an incorrect price format or a duplicated stake. Use the final figure as an aid to understanding the arithmetic, not as a reason to ignore a limit you set in advance.