Official figures — September 2026. These are the confirmed prices published by the Department of Mineral and Petroleum Resources (DMPR), effective Wednesday, 2 September 2026. Petrol 93 and 95 both rose 134 c/l, diesel 500ppm rose 294 c/l, diesel 50ppm rose 315 c/l and illuminating paraffin rose 213 c/l. The previous official prices took effect on 5 August 2026.

Managing logistics, delivery routes, or a commercial transport business in South Africa requires precise budgeting. Fuel is often the largest variable operating expense for any commercial operation. This interactive Fleet Diesel Cost Calculatorhelps you transform volatile fuel-price data into practical, actionable cost projections.

Whether you operate a single delivery vehicle or manage a large logistics operation, you can use this tool to estimate your daily, weekly, or monthly diesel expenditures based on your unique fleet metrics.

Fleet Diesel Cost Calculator Tool

Interactive Calculator Fields

Use this interface to configure your fleet metrics. All outputs provided are practical cost estimates meant for operational planning.

+-------------------------------------------------------------+
|                     VEHICLE / FLEET INPUTS                  |
+-------------------------------------------------------------+
| Total Distance to Cover:     [ 5000 ] (km)                  |
| Average Fuel Consumption:    [ 35.0 ] (Litres / 100 km)     |
| Usage Period:                ( ) Daily  ( ) Weekly  (*) Monthly |
+-------------------------------------------------------------+
|                     FUEL PRICE SETTINGS                     |
+-------------------------------------------------------------+
| Select Zone/Grade:           [ Inland - Diesel 0.005%     v ] |
| Fuel Price per Litre (R):    [ 25.67 ] (Auto-fills / Editable)|
+-------------------------------------------------------------+
|                     CALCULATE COSTS                         |
|                       [ CALCULATE ]                         |
+-------------------------------------------------------------+
|                     ESTIMATED OUTPUTS                       |
+-------------------------------------------------------------+
| Total Fuel Required:         1,750.00 Litres                |
| Total Estimated Cost:        R44,922.50                      |
| Cost Per Kilometre (CPK):    R8.98 per km                   |
+-------------------------------------------------------------+

Operational Note: This calculator provides directional estimates. True road conditions, payload weights, driver behavior, and idling times will affect actual consumption figures. To benchmark broad operations, compare these results against our dedicated fuel calculators South Africa hub.

Enter your distance, consumption and fuel price

To get an immediate, highly accurate calculation, you need to collect three essential numbers from your operations:

Current fuel-price assumptions

Diesel prices in South Africa are adjusted on the first Wednesday of every month by the Department of Mineral Resources and Energy (DMRE). Unlike petrol, which has a fixed retail price, diesel prices shown are official wholesale baselines.

The following baseline figures are the official DMRE wholesale prices effective September 2026:

Fuel Grade & Geographic ZoneWholesale Price (cents per litre / c/l)Wholesale Price (Rands per litre / R/l)
Inland – Diesel 0.05% Sulphur2,911.11 c/lR29.11 / l
Inland – Diesel 0.005% Sulphur2,955.51 c/lR29.56 / l
Coastal – Diesel 0.05% Sulphur2,823.91 c/lR28.24 / l
Coastal – Diesel 0.005% Sulphur2,868.31 c/lR28.68 / l

Our tool uses these figures as defaults, but you should adjust the price field manually if your fleet relies on independent commercial retail margins or private wholesale supplier contracts.

Worked example

Let’s look at a typical mid-sized South African logistics business operating out of Gauteng (Inland) using 50ppm diesel (Diesel 0.005% Sulphur).

Inputs Needed

Example Calculation

First, we establish the total amount of fuel required for the distance:

$$\text{Fuel Volume} = \frac{25,000 \text{ km}}{100} \times 30 \text{ L/100km} = 7,500 \text{ Litres}$$

Next, we multiply this total volume by the current wholesale price per litre to discover the projected cost:

$$\text{Total Monthly Cost} = 7,500 \text{ Litres} \times \text{R}25.17 = \text{R}188,775.00$$

To find your baseline Cost Per Kilometre (CPK) for fuel:

$$\text{Cost Per Kilometre} = \frac{\text{R}188,775.00}{25,000 \text{ km}} = \text{R}7.55 \text{ per km}$$

How the calculation works

The logic underpinning our tool mirrors standard transport logistics accounting formulas. The application processes your inputs step-by-step using two sequential mathematical formulas.

Formula Used

  1. Total Fuel Required (Litres):$$V = \frac{D}{100} \times C$$Where $V$ is the Total Fuel Volume in litres, $D$ is the Total Distance in kilometres, and $C$ is the Consumption rate in L/100km.
  2. Total Fuel Cost (ZAR):$$P = V \times R$$Where $P$ is the Total Projected Cost in Rands, $V$ is the calculated volume from the first step, and $R$ is the Fuel Price per litre.

By breaking this down, fleet managers can clearly see how even a minor $0.5\text{ L/100km}$ improvement in fuel efficiency or a minor drop in the wholesale price directly scales down total operating expenses over thousands of accumulated kilometers.

Related calculators and price pages

To keep your supply chain budget optimized against daily and monthly energy updates, use our network of specialized tools:

Frequently asked questions

What inputs does the fleet diesel cost calculator need?

The calculator requires your total planned travel distance (in kilometers), the average fuel efficiency consumption profile of the vehicle (in Litres per 100 km), and the applicable localized fuel price in R/l.

Are calculator results exact?

No. The outputs are high-precision estimates. Real-world fleet operations must account for external variances such as varying payload weights, regional traffic patterns, terrain elevations, and unexpected driver idling times.

Should inland and coastal prices be included?

Yes. Because fuel in South Africa incurs transport costs from coastal ports to the interior, inland wholesale prices are consistently higher than coastal wholesale prices. Always verify whether your fleet primarily refuels at coastal or inland stations before finalizing budgets.

How can users reduce fleet fuel costs?

Fleet owners can limit costs by monitoring real-time consumption profiles, planning routes to bypass heavy urban congestion, providing defensive driving training to lower average L/100km metrics, and matching refueling schedules with our monthly price adjustment projections.