📅 Job Duration Calculator

How to Use This Calculator

Enter your total volume, select your machine type, set your efficiency factor and schedule. The calculator shows daily and weekly production and estimated completion time.

What is the Efficiency Factor?

No machine runs at 100% capacity all day. The efficiency factor accounts for operator breaks, machine repositioning, grade changes, waiting on trucks, and minor delays. Typical values:

• 75% — good conditions, experienced crew, short hauls
• 60-70% — average conditions, mixed terrain, some delays
• 50% — difficult conditions, long cycle times, remote site
• 85%+ — exceptional — use only for short, straightforward work

Typical Production Rates

• Excavator 20t (Cat 320): 150-250 cy/hr depending on material and swing angle
• Excavator 35t (Cat 330): 300-500 cy/hr
• Excavator 50t+ (Cat 390): 500-800 cy/hr
• Dozer D6: 300-500 cy/hr pushing on good ground
• Dozer D10: 600-1,000 cy/hr bulk pushing downhill
• Rock mucking: 50-60% of soil rates

Adding Contingency

Weather, breakdowns, and unexpected site conditions typically add 15-25% to earthmoving schedules. If your calculation shows 10 days — plan for 12-13 days in your project schedule.

Multiple Machines

Add production rates together for multiple machines working the same area. Two Cat 330s = roughly 800 cy/hr combined (at 75% efficiency each). Note: diminishing returns if machines interfere with each other's work areas.