Event Dishwashing & Pot Wash Trailer Calculator

How Many Dishwashers Do I Need for My Event?


Planning a wedding, festival, corporate event or large-scale catering operation? Our free event dishwashing calculator helps estimate the washing capacity required to keep your event running smoothly.


Simply enter your guest numbers, service duration, crockery, glassware and cutlery requirements. Our calculator estimates the total wash load, required washing speed, crockery stock buffer and approximate detergent and rinse aid consumption.


Our mobile dishwashing and pot wash trailers are equipped with professional Winterhalter dishwashing equipment, including PT-M and UC-M machines, suitable for a range of commercial catering applications.


Onsite Refrigeration provides mobile dishwashing trailer hire for weddings, festivals, film and television productions, commercial kitchens and temporary catering facilities across London, Surrey, the South East and further afield.


All calculations are estimates. Our team can confirm the appropriate setup based on your event requirements, available utilities and site conditions.

Dishwashing Trailer Calculator

Estimate whether our mobile pot wash trailer is suitable for your event, plus approximate detergent and rinse aid requirements.

Use the busiest washing period for peak events. For continuous service, use the full operating time.
Use whole numbers only.
Use 0 if glasses are not required.
1 set = knife/fork/spoon group.
Adds extra wash load for kitchen equipment.
Includes clearing tables, loading, washing, drying and returning items ready for use — not just the machine wash cycle.
Typical ranges: 20–30 mins (fast), 30–60 mins (normal), 60–90 mins (busy events).
Enter 0 if unknown.
Enter 0 if unknown.
Enter 0 if unknown.
Machine capacity used:
PT-M: up to 55 racks/hour
UC-M: up to 40 racks/hour
These are fixed machine ratings and cannot be increased by the customer.

This is an estimate only. Final setup depends on site access, water, waste, power, menu, glassware, crockery and turnaround speed.

Your estimate will appear here

Enter your event details and calculate.

Estimated total items —
Estimated racks —
Required wash rate —
Estimated wash time —
Detergent estimate —
Rinse aid estimate —

Stock buffer check

Plates — —
Glasses — —
Cutlery sets — —

This estimates the minimum stock needed in circulation based on your reuse cycle.

Based on normal dosing – actual use may vary depending on water conditions, loading and site setup.

Get a confirmed setup for your event

Send this estimate to us and we’ll confirm the correct dishwashing setup, including power, water and chemical requirements.

Check availability for your date
No estimate calculated yet.