Calculating work hours is based on a simple formula: departure time minus arrival time, minus breaks. The difficulty lies not in the operation itself, but in the regularity of tracking and the legal value of the records produced. Between a loose sheet, a spreadsheet, and a time tracking software, each method presents significant discrepancies in terms of reliability, time spent, and admissibility in case of disputes.
Probative Value of Hourly Records: What Recent Case Law Says
An hourly record does not need to be perfect to be admissible before labor courts. Since a ruling by the Court of Cassation on September 24, 2025 (n° 24-17.141), records indicating daily hours and the weekly total are sufficient to compel the employer to provide their own control elements.
This means that a simple table, even maintained on paper or in a spreadsheet, can constitute a starting point for evidence. Late emails, SMS messages, or file recording times can complement the file.
For employees looking for how to calculate their work hours on Make It Now, this legal dimension is rarely addressed, even though it conditions the choice of tracking method.
Article L. 3171-2 of the Labor Code requires the employer to justify the hours actually worked. However, no specific tool is legally mandatory: badge systems, spreadsheets, or paper sheets have the same validity, provided that the count is reliable and verifiable.
Comparison Table of Tools for Calculating Work Hours
The choice of a tool depends on the size of the team, the budget, and the level of proof sought. Here is a comparison of the three main methods.
| Criteria | Paper Sheet | Spreadsheet (Excel, Sheets) | Time Tracking Software |
|---|---|---|---|
| Cost | Free | Free or very low | Monthly subscription |
| Reliability of Count | Low (frequent input errors) | Medium (automated formulas, manual input) | High (automatic timestamping) |
| Probative Value | Admissible if regular | Admissible if dated and consistent | Admissible, but must be tamper-proof |
| Risk of Falsification | High | Medium (traceable modifications depending on the tool) | Low if the system is properly configured |
| Suitable for | 1 to 5 people | 5 to 30 people | Any company size |
The paper sheet remains relevant for a freelancer or a very small structure. The spreadsheet offers a good compromise for medium-sized teams. Time management software becomes cost-effective as payroll calculations and tracking of overtime require several hours per month.
Excel or Google Sheets: The Concrete Limits of Manual Calculation
A well-constructed spreadsheet automatically calculates daily and weekly work duration. The basic formula remains the same: end time minus start time minus break. In Excel, the time format (hh:mm) requires cells to be set up correctly, or else it may display negative or inconsistent results.
The real problem with the spreadsheet is not the calculation, but the input. An employee filling in their hours at the end of the week reconstructs from memory, which introduces approximations. Over a full month, these accumulated discrepancies can represent several tens of minutes.
- Formulas do not detect input omissions: an empty row goes unnoticed without visual control
- The spreadsheet does not automatically distinguish overtime from regular hours unless conditional formulas are manually added
- Sharing the file between manager and employee creates risks of concurrent versions, especially on local Excel
Google Sheets mitigates this last problem thanks to the timestamped version history. Each modification is tracked with the date and author, which enhances the document’s value in case of disputes.
Common Pitfall with Time Format
In Excel, a duration that exceeds 24 hours (typically a weekly total) displays incorrectly if the cell format remains “hh:mm”. You must use the custom format [h]:mm for the total to display correctly. This common error skews the weekly duration count and can lead to discrepancies in calculating overtime.
Time Tracking Software: Reliability and Regulatory Constraints
Time tracking software automates timestamping and eliminates manual input. Payroll service productivity improves, as the data is directly usable for salary calculations and overtime management.
However, automation does not guarantee everything. A time tracking system must be reliable and tamper-proof for the employer to rely on it. If the software allows modifications to timestamps afterward without traceability, its probative value collapses.
Tools that use biometrics (fingerprint, facial recognition) are subject to specific constraints from the CNIL. An employee can refuse a biometric device, and the employer must then offer an alternative. The simple badge remains the most common and least legally exposed solution.
- Check that the software keeps an unmodifiable history of timestamps
- Ensure that employees can view their own data in real-time
- Provide a structured correction procedure (manager validation) for missed clock-ins
- Control the GDPR compliance of the provider, especially regarding data retention duration
Overtime and Monthly Calculation: Adapting the Method to the Contract
The monthly calculation of work hours is not simply multiplying weekly hours by four. The average number of weeks per month is 4.33, which explains the discrepancies between the weekly total and the total on the payslip.
For part-time employees, the calculation must reflect the contractual duration and not the legal duration. Complementary hours (beyond the contract but below the legal duration) follow different rules for increases compared to standard overtime.
Regardless of the chosen tool, the count must be consistent with the mentions on the payslip. A recurring discrepancy between the employee’s record and the payslip constitutes a warning signal that justifies a thorough check, or even a formal request to the employer.
The most suitable calculation method depends less on technology than on the rigor of input and the regularity of tracking. A spreadsheet updated daily protects better than a sophisticated software that no one verifies the data for.
