Odds Converter for Excel

Q: How do I display American odds with a leading plus sign?

Wrap the formula in an IF that prefixes a plus sign for positive results, or set the cell's number format to +0;-0 to apply the sign without using a formula.

Q: How do I handle the case where the input cell is empty?

Wrap the formula in IF(A2 = "", "", your formula). This keeps blank input cells from returning #DIV/0! or #NUM! errors.

Q: Where can I see this math run live without Excel?

The main odds converter on odds-converter.net runs the same formulas in your browser, and the Dutching calculator handles multi-way stake distribution without a spreadsheet.

Suggested sheet layout

By Matt Hodson | Last reviewed May 2026

The formulas below all assume your input value sits in cell A2 and any second input (such as a stake) sits in B2. Adjust the cell references to match your sheet. All formulas use only the standard library, no add-ins or LET() features, so they work in Excel 2007 and up as well as Google Sheets.

American to Decimal

Input: American odds in A2 (e.g. +150 or -200). Output: decimal odds.

=IF(A2>=100, A2/100 + 1, IF(A2<=-100, 100/ABS(A2) + 1, NA()))

Decimal to American

Input: decimal odds in A2 (e.g. 2.50). Output: American odds, rounded to a whole number.

=IF(A2>=2, ROUND((A2 - 1) * 100, 0), IF(A2>1, ROUND(-100 / (A2 - 1), 0), NA()))

To show the result with a leading + sign on positive lines, wrap the formula:

=IF(A2>=2, "+" & ROUND((A2 - 1) * 100, 0), ROUND(-100 / (A2 - 1), 0))

Decimal to Implied Probability

Input: decimal odds in A2. Output: implied probability as a number between 0 and 1. Format the cell as a percentage.

=1 / A2

Implied Probability to Decimal

Input: implied probability in A2 as a decimal fraction (e.g. 0.40 for 40%). Output: decimal odds.

=1 / A2

If the input is a whole-number percentage (40 for 40%), use:

=100 / A2

American to Implied Probability

Input: American odds in A2. Output: implied probability between 0 and 1.

=IF(A2>=100, 100 / (A2 + 100), IF(A2<=-100, ABS(A2) / (ABS(A2) + 100), NA()))

Implied Probability to American

Input: implied probability in A2 as a decimal fraction (e.g. 0.40). Output: American odds, rounded.

=IF(A2<=0.5, ROUND((1 - A2) / A2 * 100, 0), ROUND(-A2 / (1 - A2) * 100, 0))

Decimal to Fractional (display only)

Excel does not natively reduce fractions cleanly for arbitrary decimal odds, but it can approximate. Input: decimal odds in A2. Output: a fractional string.

=SUBSTITUTE(TEXT(A2 - 1, "# ?/?"), " ", "")

For a fixed denominator of 100 (no reduction):

=ROUND((A2 - 1) * 100, 0) & "/100"

Fractional to Decimal

If the numerator is in A2 and the denominator is in B2:

=A2 / B2 + 1

If the fractional value is stored as a text string in A2 (e.g. "3/2"):

=VALUE(LEFT(A2, FIND("/", A2) - 1)) / VALUE(MID(A2, FIND("/", A2) + 1, 99)) + 1

Payout and Profit

Input: stake in B2, decimal odds in A2.

Total return:  =B2 * A2
Profit:        =B2 * (A2 - 1)

From American odds in A2 and stake in B2:

Profit:        =IF(A2>=100, B2 * A2 / 100, B2 * 100 / ABS(A2))
Total return:  =B2 + IF(A2>=100, B2 * A2 / 100, B2 * 100 / ABS(A2))

No-vig Price (two-way market)

Input: implied probability of side A in A2, side B in B2, both as decimal fractions. Output: the fair no-vig probability for side A.

No-vig side A:  =A2 / (A2 + B2)
No-vig side B:  =B2 / (A2 + B2)
Overround %:    =(A2 + B2 - 1) * 100

Combined book percentage (multi-way market)

Implied probabilities for each side in the range A2:A10:

=SUM(A2:A10) * 100

A value below 100% across that range means the combined market offers an arbitrage. A value above 100% is the normal sportsbook margin.

Dutching: stake per selection

Sheet layout: total stake in F1. Decimal odds for each selection in B2:B7. Add a helper column C with the inverse odds, and a single sum cell.

Cell C2 (drag down):      =1 / B2
Cell C8 (sum of inverses): =SUM(C2:C7)
Cell D2 (stake, drag down): =$F$1 * C2 / $C$8
Cell E2 (return, drag down): =D2 * B2
Cell F2 (total return):     =$F$1 / $C$8
Cell F3 (profit):           =F2 - $F$1

The return is identical for every winning selection. If F2 is greater than F1, the combined market is an arbitrage; otherwise the Dutched bet has a fixed negative expected value equal to the sportsbook vig.

Break-even win rate

Input: decimal odds in A2. Output: the minimum win rate required to break even at this price, formatted as a percentage.

=1 / A2

From American odds:

=IF(A2>=100, 100 / (A2 + 100), ABS(A2) / (ABS(A2) + 100))

Excel Odds Conversion FAQ

Do these formulas work in Google Sheets?

Yes. None of them use Excel-only features. They work in Google Sheets, Excel for the web, and LibreOffice Calc without modification.

How do I display American odds with a leading plus sign?

Wrap the formula in an IF that prefixes "+" for positive results: see the second formula in the Decimal to American section above. You can also set the cell's number format to +0;-0 if you want the sign without using a formula.

Why does the Decimal to Fractional formula sometimes look wrong?

Excel's built-in fraction format approximates over small denominators by default. For exact reduced fractions on arbitrary decimal odds, you would need a small UDF (VBA macro) that runs Euclid's algorithm. The fixed-denominator /100 form above is exact and works without macros.

How do I handle the case where the input cell is empty?

Wrap the formula in IF(A2 = "", "", <your formula>). This keeps blank input cells from returning #DIV/0! or #NUM!.

Where can I see this math run live without Excel?

The main odds converter on this site runs the same formulas in your browser, and the Dutching calculator handles multi-way stake distribution without a spreadsheet.