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OEE Calculator

Overall Equipment Effectiveness — full loss breakdown & Six Big Losses

01

Time & Production Inputs

Minutes unless noted. Calculated values are greyed-out and auto-filled.

Time Values
Total scheduled production window
Machine was actually running
Scheduled maintenance & changeovers
Used to derive MTBF & MTTR
Production Values
Standard time per part at rated speed
02

OEE Metrics

Overall Equipment Effectiveness
76.8
%
World-class OEE is ≥85%
OEE = A × P × Q
Availability Percentage of planned production time that the machine was actually running. Unplanned downtime (breakdowns) reduces this value. A
87.5
%
Runtime ÷ (PPT − Planned DT)
Performance How fast the machine runs compared to its ideal speed. Minor stops and slow cycles reduce this value. P
90.6
%
(Ideal Cycle × Pieces) ÷ Runtime
Quality Percentage of produced units that meet quality standards. Defects, scrap, and rework reduce this value. Q
99.0
%
Good Pieces ÷ Total Pieces
MTBF (Mean Time Between Failures)
—
min / breakdown
Uptime ÷ Breakdown Count
MTTR (Mean Time To Repair)
—
min / breakdown
Unplanned DT ÷ Breakdown Count
03

Loss Breakdown — Six Big Losses

All losses are derived from the inputs above and expressed as a percentage of Planned Production Time.

Availability Losses Unplanned + Planned
Unplanned Downtime (Breakdowns) —
Planned Downtime (Maintenance) —
Total Availability Loss —
Performance Losses Minor Stops + Speed
Minor Stops & Idling —
Speed Loss (Reduced Rate) —
Total Performance Loss —
Quality Losses Startup + Production
Startup Defects (Warm-up) —
Production Rejects (Scrap) —
Total Quality Loss —
04

Loss Visualisation

Longest bar = 100%. Each individual loss is shown relative to the largest loss. Total loss shown as ■ red segment.

World-class
Needs improvement
Unplanned Downtime —
Planned Downtime —
Minor Stops & Idling —
Speed Loss —
Startup Defects —
Production Rejects —
Total Loss (1 − OEE) —
0% 25% 50% 75% 100%
05

Formula Reference

Core Metrics
OEE= Availability × Performance × Quality
Availability= Runtime ÷ (PPT − Planned Downtime)
Performance= (Ideal Cycle Time × Total Pieces) ÷ Actual Runtime
Quality= Good Pieces ÷ Total Pieces
MTBF= Uptime ÷ Number of Breakdowns
MTTR= Downtime ÷ Number of Breakdowns
Six Big Losses
A-Loss (BD)= (Unplanned Downtime ÷ PPT) × 100%
A-Loss (PM)= (Planned Downtime ÷ PPT) × 100%
P-Loss (MS)= (Minor Stop Time ÷ PPT) × 100%
P-Loss (Spd)= (Speed Loss Time ÷ PPT) × 100%
Q-Loss (SD)= (Startup Defects ÷ Total Pieces) × 100%
Q-Loss (PR)= (Rejects ÷ Total Pieces) × 100%
Current Calculation
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