Calculated Result
Enter values below and calculate.
Lead Time Inputs
Lead Time Comparison
Add suppliers, orders, or projects to compare performance.
| Supplier / Owner | SKU / Task | Start | Completion | Calendar | Working | Planned | Variance | Status | Action |
|---|
Lead-Time Trend
Historical values appear first, followed by comparison records added during this session.
Understanding Lead Time
Lead time measures how long a process takes from initiation to completion. Businesses use it for purchasing, manufacturing, order fulfillment, logistics, project work, and customer delivery planning. A clear lead time estimate improves scheduling because teams can decide when orders must start to meet a required completion date. It also helps inventory planners reduce shortages, avoid unnecessary stock, and compare supplier performance consistently.
Formula Used
The simplest formula is Lead Time = Completion Date − Start Date. Component-based planning adds every stage that contributes to the total. A practical model is processing time plus waiting time plus setup time plus production time plus inspection time plus packaging time plus shipping time plus safety buffer. This calculator supports both approaches. Calendar days measure continuous elapsed time, while working-day calculations can exclude weekends, custom non-working days, and listed holidays.
How to Use This Calculator
Choose the lead time category and calculation mode first. For date-based calculations, enter the order date and actual completion date. Add a planned date when variance analysis is required. For component-based calculations, enter each duration and a start date. Select whether the schedule uses calendar days, weekdays, or a custom workweek. Add holidays that should not count as working days. The result shows calendar lead time, working lead time, estimated completion, variance, and delivery status.
Supplier comparisons are useful when multiple vendors quote different processing and transit durations. Add each completed calculation to the comparison table. Average, minimum, maximum, and median values update automatically. Export the results as CSV for spreadsheet analysis or PDF for reporting. Variance highlights whether actual or estimated lead time exceeds the plan. Positive variance indicates delay, while negative variance indicates earlier completion. Regularly tracking these values can reveal bottlenecks, unreliable suppliers, and opportunities to reduce waiting. Accurate lead-time records support better purchasing decisions and service expectations. Consistent measurements make operational planning clearer and more dependable.
Example Lead Time Data
| Scenario | Processing | Production | Transit | Buffer | Total |
|---|---|---|---|---|---|
| Local supplier | 1 day | 2 days | 1 day | 1 day | 5 days |
| Regional supplier | 2 days | 3 days | 2 days | 1 day | 8 days |
| International supplier | 3 days | 5 days | 10 days | 2 days | 20 days |
Frequently Asked Questions
What is lead time?
Lead time is the elapsed duration between starting a process and reaching its completion or delivery point.
What is the difference between calendar and working lead time?
Calendar lead time counts every day. Working lead time excludes non-working days according to the selected schedule and holidays.
Can I calculate an estimated completion date?
Yes. Component-based mode adds the total duration to the selected start date using your chosen working-day rules.
How is lead-time variance calculated?
Variance equals actual or estimated lead time minus planned lead time. Positive values indicate delay, and negative values indicate early completion.
Can I compare multiple suppliers?
Yes. Add each calculation to the comparison table to review averages, minimums, maximums, medians, variances, and status.
Do CSV and PDF exports include comparison rows?
Yes. Both exports include the current result and any comparison rows added during the session.