Free shipping calculator
Demurrage & Detention Calculator
Enter the contractual start and end dates, free days, rate tiers and fixed charges. The calculator shows elapsed, free and chargeable days separately so an arrival notice or carrier invoice can be checked without hidden date arithmetic.
Estimated time-based charges
USD 0
0 elapsed calendar days less 5 free days = 0 chargeable days. Tier 1: 0 days / USD 0; later tier: 0 days / USD 0; fixed charges USD 0.
Date-counting conventions differ by carrier, terminal, equipment event and jurisdiction. Confirm whether the start day is included, whether free time uses calendar or working days, and whether demurrage, detention and storage are billed separately before relying on this audit.
Recommended next step
Check dates and free time against the arrival notice before disputing charges.
What this tool helps you check
- Separate free and chargeable days
- Model tiered daily rates
- Audit a carrier invoice
- Document the date basis used
Calculation method
Elapsed calendar days are calculated from the selected start and end dates, free time is deducted, and remaining days are allocated through the entered rate tiers before fixed fees.
Contracts differ on inclusive dates, holidays, start events, combined free time and local rules. Confirm the governing tariff or service contract.
Frequently asked questions
Is the Demurrage & Detention Calculator free to use?
Yes. The calculator is available without an account, and values entered into the form are calculated in the browser or by the tool endpoint required for the lookup.
How does the Demurrage & Detention Calculator work?
Elapsed calendar days are calculated from the selected start and end dates, free time is deducted, and remaining days are allocated through the entered rate tiers before fixed fees.
Can I use the result for a booking or invoice approval?
Use the result as a transparent working calculation and verify it against the governing carrier tariff, contract or operational requirement. Contracts differ on inclusive dates, holidays, start events, combined free time and local rules. Confirm the governing tariff or service contract.