Free Lead Time Calculator
Add up the stages of your lead time into a single total, see which stage takes the longest, and turn the total into an expected delivery date in calendar or working days, with a buffer for the days things slip.
Padding for delays.
When the order is placed.
Every day counts.
Public holidays to add.
About 3 weeks across 4 stages, plus a 2.1 days buffer.
A quick estimate for planning. Confirm the stage times with your suppliers and carriers before you commit to a date.
Your lead time in four steps.
List the stages, enter how long each takes, and the tool adds them into a total, shows where the time goes, and works out the delivery date. Everything updates as you type.
List your stages
Break your lead time into stages, like order processing, production, transit and receiving. Add or remove stages to match your process.
Enter each duration
Put in how long each stage takes, in days or weeks. The tool adds them into a single total lead time as you type.
See where the time goes
A breakdown shows each stage as a share of the total and lays it out on a timeline, so you can spot the slowest step at a glance.
Get your delivery date
Add an order date and choose calendar or working days to see when the order should arrive, with an optional buffer for delays.
Know your lead time, keep your promises.
Lead time drives the dates you promise, the stock you hold and when you reorder. Getting it right keeps customers happy and shelves stocked.
Spot the bottleneck
The breakdown shows which stage eats the most time, so you know where to push for a faster turnaround instead of guessing.
Promise realistic dates
Turn a lead time into an actual delivery date in working days, so the dates you give customers and your own team hold up.
Plan safer reorders
A longer or more variable lead time means you should reorder earlier. Add a buffer to stay ahead of delays and avoid stockouts.
How lead time adds up.
The formulas behind the tool, with a worked example. Lead time is the sum of its stages, and it feeds straight into your delivery dates and reorder points.
Total lead time
Lead time = Processing + Production + Transit + Receiving
Example: Stages of 2, 10, 7 and 2 days add up to a total lead time of 21 days.
Supply and reorder view
Lead time = Supply delay + Reordering delay
Example: If a supplier takes 18 days to fulfil and you reorder every 3 days, the effective lead time is about 21 days.
Expected delivery date
Delivery date = Order date + Lead time (working days)
Example: An order placed on a Monday with a 21 working day lead time arrives about four weeks later, skipping weekends.
Lead time demand
Lead time demand = Daily demand × Lead time
Example: At 40 units a day and a 21 day lead time, you need about 840 units to cover the wait, which sets your reorder point.
Lead times that track themselves.
A single estimate is a great start. Across many suppliers and products, you want a system that measures real lead times from your order history, flags the ones slipping, and reorders at the right moment. That is the kind of inventory, ERP and procurement software we build at Techliphant, shaped around how your business actually works.
Setting your reorder point? Try the EOQ calculator.
Common lead time questions.
Lead time is the total time from placing an order to receiving it, or from starting a process to finishing it. In supply chains it usually covers everything from raising a purchase order to the goods arriving and being ready to use, including processing, production, shipping and receiving.
The simplest version adds up the stages: Lead time = order processing + production + transit + receiving. Another common framing is Lead time = supply delay + reordering delay, where supply delay is how long the supplier takes to fulfil an order and reordering delay is the gap between your orders. This calculator uses the stage based method and lets you add or remove stages.
Add the time each stage takes. Say order processing is 2 days, production is 10 days, transit is 7 days and receiving is 2 days. The total lead time is 2 + 10 + 7 + 2 = 21 days. If you place the order on the 1st, and count in calendar days, you can expect it around the 22nd.
Common components are order or processing time, production or manufacturing time, transit or shipping time, and receiving or inspection time. You will also see terms like material lead time (waiting on raw materials), supplier lead time (the vendor side), and customer lead time (order to delivery from the buyer's point of view). This tool lets you name and add whichever stages fit your process.
Lead time is the whole clock, from order to delivery, including any waiting and queueing. Cycle time is only the hands on part, the actual time spent working on the item. Cycle time is always a portion of lead time, and reducing waiting between stages is often the fastest way to cut lead time without changing cycle time.
Use calendar days when the clock keeps running over weekends, such as long international shipping. Use working days when the work only happens on business days, such as production or local dispatch. This calculator lets you switch between the two and add a number of public holidays, so the delivery date reflects how your operation actually runs.
The longer the lead time, the more stock you burn through while waiting, so you must reorder earlier. Lead time demand is your daily demand times the lead time, and that sets your reorder point. If lead time is variable, you add safety stock on top as a buffer. Our EOQ calculator works out the reorder point once you know your lead time.
Real lead times vary. Suppliers slip, shipments get delayed, and holidays get in the way. A buffer, as a percentage or a fixed number of days, pads your expected lead time so the dates you commit to are realistic even on a bad run. The tool shows both the expected date and the buffered date.
Start with the breakdown and attack the biggest stage. Common moves are ordering more frequently in smaller batches, holding safety stock of long lead items, qualifying a second supplier, moving production or stock closer to customers, and cutting the waiting and approval gaps between stages. Even small cuts to the slowest stage move the total the most.
Yes on both. It is free, there is no sign-up, and it runs entirely in your browser. Nothing you type is sent anywhere or saved, so your figures stay on your own device.
It is great for a quick estimate on a single product or supplier. If you are tracking lead times across many suppliers and products, with real order history, variability and automatic reorder points, you want inventory or ERP software that measures it for you. That is the kind of system we build at Techliphant, shaped around how your business actually works.
Private by design: this calculator runs entirely in your browser, so nothing you type is uploaded or stored. It is provided free for quick estimates and planning. Real lead times vary, so treat the result as a guide, add a buffer, and confirm with your suppliers and carriers before you commit.
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