A Spreadsheet Formula for Converting Time to Decimal Hours
October 23, 2026
In both Excel and Google Sheets, a cell formatted as a time value (such as 7:30 for 7 hours 30 minutes) is actually stored internally as a fraction of a 24-hour day — multiplying that cell by 24 converts it directly into decimal hours.
Skip the math and get your answer instantly:
Open the Decimal Hours Converter →The Formula
If cell A1 contains a time value like 7:30 (formatted as time), the formula =A1*24 in another cell returns 7.5 — the decimal hours equivalent.
Why This Works
Spreadsheet time values are internally stored as a fraction of a full day (24 hours) — 7:30 is stored as roughly 0.3125 (7.5 ÷ 24). Multiplying by 24 reverses that internal storage format back into a human-readable decimal hours figure.
A Common Gotcha
If the source cell is formatted as plain text (like "7:30" typed as a string, not a recognized time value), the multiplication formula won't work correctly — confirming the cell is actually formatted and recognized as a time value by the spreadsheet software is a necessary first step before applying this formula.
Frequently Asked Questions
What's the spreadsheet formula to convert a time value to decimal hours?
Multiply the time-formatted cell by 24, e.g., =A1*24.
Why does multiplying by 24 work?
Because spreadsheet time values are internally stored as a fraction of a 24-hour day, so multiplying by 24 converts that fraction back into decimal hours.
What's a common issue with this formula?
If the source cell is plain text rather than a recognized time value, the formula won't calculate correctly.
Does this formula work the same in Excel and Google Sheets?
Yes — both store time values the same underlying way, so the ×24 formula works in either.