Rekenbox · 2026
Fuel surcharge calculator
Apply a fuel price change to your own trip or hourly rate.How your result is built
From base rate to new rate
The rate rounded to cents is multiplied by 8 units.
- Base rate
- €80.00
- Surcharge or decrease per unit
- €3.64
- Difference across all units
- €29.12
- Fuel price change (%)
- 18.18
Assumptions, sources and version
2026 · nl-2026.1 · v2026.1
- Linear index method: rate change = (new fuel price / base fuel price − 1) × fuel share. The share applies on the base date. Use only if this method matches your agreement.
- Your own prices, not a live diesel index. The adjusted unit rate is rounded to cents first; the order amount uses that rate. No automatic VAT calculation or legal assessment of your contract.
- Cumela — brandstoftoeslag en clausule (2026-09-06)
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Understand your result
How this tool works
The base rate changes by the relative fuel-price change multiplied by the fuel share. The new unit rate is rounded to cents before calculating the total. Use the same VAT basis for both fuel prices. Choose whether lower prices produce a discount. This is a linear model; your contract determines the actual agreement.
Common questions
Is this a mandatory surcharge?
No. This model helps calculate an agreement. There is no universal surcharge for every transport contract.
Which fuel price should I use?
Use the reference source and measurement period in your agreement. Compare both prices including VAT or both excluding VAT.
Which details do you need?
- Agreed base diesel price (€/litre) — Use the same VAT basis and unit for both prices. Up to four decimals.
- New diesel price (€/litre)
- Fuel share of your base rate (%)
- Base rate excluding VAT (€)
- Rate unit
- Number of units
- Also pass on a price decrease
Limits of this tool
- Linear index method: rate change = (new fuel price / base fuel price − 1) × fuel share. The share applies on the base date. Use only if this method matches your agreement.
- Your own prices, not a live diesel index. The adjusted unit rate is rounded to cents first; the order amount uses that rate. No automatic VAT calculation or legal assessment of your contract.
Year: 2026 · Version 2026.1
Sources for this tool
- Cumela — brandstoftoeslag en clausule · calculation source checked 2026-09-06
Prepared by the Rekenbox product team at Winstwaker. The listed source references and calculation version make the method traceable. Report a content error Last updated: 2026-09-06. Rekenbox is a product by Winstwaker. The tool applies a calculation model to your inputs; a result or paid report is not a personal assessment by an adviser.