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's arithmetic on the numbers you entered. Market rules, settlement mechanics and price movement all change how a real bet lands.

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 shows the arithmetic. It doesn't tell you whether the price fits your read of the outcome or your budget. Decide the stake before you enter it. Check the market rules. Keep essential money out of it entirely.

Cross-check on a second tool. The calculator hub, Parlay odds or Break even win rate cover the same numbers from a different angle. Same price conventions, so a decimal price in one is a decimal price in the other.

Read the odds format guide if you're new to the formats. Two minutes.

Reading a rounded result

Money is rounded to two decimals here. A real settlement applies its own rounding sequence, which can differ. Keep the original inputs written down if you're going to check the number later.

Unclear about an input? Find the stated market term. Don't guess. A quick sanity check: change one input by a small amount and see whether the result moves the way you expect.

That doesn't validate the market. It can flag a reversed sign, a mis-entered price format or a duplicated stake. Use the number to understand the arithmetic. It's not a reason to ignore a limit you set in advance.