Profit Hawk
Free tool · For Amazon FBA sellers

Amazon Reorder Lead Time
Calculator.

Add up every stage from PO to FBA shelf — production, freight, customs, prep, ground, and Amazon receiving — and stop using your supplier's 30-day brochure number as if it's the whole story.

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What question does this answer
“How long does it really take from placing a PO to having inventory available at Amazon FBA?”
1

Add up every stage from PO to FBA shelf

Be honest. Every step counts — especially the ones you'd rather not think about.

days
days
days
days
days
days
days
days
Your total reorder lead time
84days
Raw lead time
77days
Planning buffer
7days
Where the 84 days come fromstage breakdown
Production30d
Supplier prep & packing5d
Freight25d
Customs clearance4d
3PL / prep center5d
Ground to Amazon3d
FBA receiving5d
Planning buffer7d
2
Next ↓ keep going
Get the latest day you can place this PO & a calendar reminder
2

When's the latest day I can place this PO?

Drop in your current stockout date and we'll work backwards to your reorder deadline.

Use the projected date your current available inventory (FBA + AWD + 3PL + inbound) runs out at your real daily sales velocity.
↗ We'll email this date back as a calendar reminder.

Your reorder deadline · sent to you

Email me my reorder deadline + a calendar reminder

Pick a stockout date on the left, then drop your email — we'll send the deadline with a calendar invite and a 7-day heads-up.

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Lead time
84days
  • Calendar invite (.ics) — Google · Outlook · AppleDate
  • 7-day reminder email — heads-up before the deadlineEmail
  • PDF of this calc — full stage breakdownPDF
  • Multi-SKU template — same plan for every SKUSheet
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How it works

Every step counts.

Reorder lead time isn't a single number — it's a chain. Each link adds days. Skip one and your safety stock runs out exactly when the PO finally lands.

Lead Time =Production+Prep+Freight+Customs+3PL+Ground+FBA Receiving+Buffer
P + S
Production & supplier prep. Manufacturing plus inspection, labeling, and cartoning before the freight forwarder picks up.
F + C
Freight & customs. Time in transit plus customs clearance. See lead-time variability for why averages lie here.
3PL + G
Prep center & ground to Amazon. Repalletizing, FNSKU labeling, then LTL or parcel to the assigned FC.
FBA
Receiving / check-in. The step almost everyone skips. Units showing 'delivered' are not yet sellable.
B
Planning buffer. A small absorber for normal slippage that doesn't deserve its own line item.

Worked example

A typical China-to-US ocean route into Amazon FBA, with a US prep center in the middle.

Production30 days
Supplier prep5 days
Ocean freight (door-to-door)25 days
Customs clearance4 days
Prep center / 3PL5 days
Ground to Amazon FC3 days
FBA receiving5 days
Planning buffer7 days
Planned lead time
84 days

Not 30 days. Not 60 days. 84 days — and that's the number your reorder point and safety stock should use.

Watch out for

Common lead-time mistakes.

These are the assumptions we see kill replenishment plans across Amazon catalogs — usually right when the PO finally lands.

01

Ignoring FBA receiving time

Units showing 'delivered' aren't sellable. Amazon's check-in step routinely adds 3–10 days, more during peak. Sellers who skip this one almost always stock out right as the PO lands.

Fix: Include 3–7 days of FBA receiving as a standing line item — even for fast-receiving FCs.
02

Only counting production days

“Lead time is 30 days” is a supplier brochure number. The real PO-to-FBA cycle adds 40–60 days of freight, customs, prep, ground, and receiving on top.

Fix: Plan against the full chain, not the manufacturing step alone.
03

Using the average instead of the worst case

Suppliers love averages. Your reorder point doesn't model lead-time variability — so when you plug in the average and it runs long, you stock out.

Fix: Use the P80 or P90 of your last 6 POs, or your worst realistic case.
04

Forgetting customs delays

Customs is fine until it isn't. A documentation error, a random exam, or a new tariff schedule can add 7–14 days with no warning.

Fix: Build a small customs buffer in, even if your last few shipments cleared in 2 days.
05

Ignoring prep center / 3PL turnaround

If you go through a US prep center for FNSKU labeling, repalletizing, or kitting, that's another 3–7 days that doesn't show up on the freight tracking.

Fix: Get your prep center's actual cycle time and plug it in as its own stage.
06

Treating peak season the same as the rest of the year

Q4 freight, Lunar New Year factory closures, and Prime Day-adjacent FC congestion all stretch lead time materially.

Fix: Maintain a seasonal lead-time profile per SKU and switch to it 6–8 weeks before peak.
When this calculator isn't enough

Great for one SKU.
Brutal for a whole catalog.

This tool nails the lead time for a single SKU on a single route. But real catalogs have multiple suppliers, multiple modes, seasonal shifts, and lead times that drift mid-PO.

  • Multi-supplier blendingIf a SKU is dual-sourced (air for emergencies, ocean for replenishment), a single lead time number under- or over-buffers depending on which one you used.
  • Stage-level varianceEach step (freight, customs, FBA receiving) has its own variability. A single average smooths over the stage that's actually killing you.
  • Seasonal & geopolitical driftPort congestion, tariff changes, supplier closures — these don't show up in a static calculator until you've already stocked out.
  • FBA, AWD & 3PL togetherReplenishment paths through AWD vs. direct-to-FBA have different effective lead times. A spreadsheet can't track both per SKU.
  • Recalculating across hundreds of SKUsManual math doesn't scale. Every supplier or freight change ripples through every SKU it touches.
  • Catching slippage before it stockouts youKnowing your average lead time isn't useful if you don't know when this PO is running late.
▲ Profit Hawk

Track lead times automatically across every SKU.

Profit Hawk connects to your Amazon Seller Central and watches the full PO-to-FBA pipeline — including FBA receiving — so your replenishment plan reflects what's actually happening, not last quarter's averages.

  • Per-SKU, per-route lead time profiles
  • Live FBA receiving & inbound tracking
  • Seasonality & supplier slippage alerts
  • Automated replenishment planning
Start free trialSee Profit Hawk →
FAQ

Reorder lead time, answered.

What sellers actually want to know — including the FBA receiving question that catches almost everyone.

What's the difference between supplier lead time and reorder lead time?
Supplier lead time usually only covers production at the factory. Reorder lead time is the full PO-to-FBA-shelf cycle: production, supplier prep, freight, customs, prep center / 3PL, ground shipping to Amazon, and FBA receiving. Reorder lead time is almost always 2–3× supplier lead time, and it's the number you should size safety stock and reorder points against.
Why include FBA receiving / check-in time?
Because Amazon's check-in step is unpredictable and frequently runs 3–10 days even after your truck arrives at the fulfillment center. Units that are 'delivered' aren't yet sellable. Skipping receiving time is the single most common reason sellers stock out exactly when their PO finally lands.
Should I use my average or worst-case lead time?
Use a realistic worst case. The classic reorder-point formula only models demand variability, not lead-time variability. The simplest way to absorb the lead-time half of the risk is to plug in the slow end of your last 6 POs — say P80 or P90 — rather than the average.
Do I really need the buffer days field?
If you trust every stage estimate above and you're tracking variability separately (in safety stock), you can leave it at zero. Most sellers find that adding 5–10 buffer days absorbs the normal-case slippage that doesn't deserve its own line item — port congestion, an Amazon receiving backup, a holiday closure at the factory.
How is this different from the Reorder Point Calculator?
The Reorder Point Calculator asks at what inventory level you should place your next PO. This one tells you how long that PO takes to land. Use this calculator first to get an honest lead-time number, then plug that number into the Reorder Point Calculator so your trigger reflects reality.
What about 3PL and AWD inventory?
AWD doesn't change door-to-FBA lead time materially — it just moves where units wait. But it does change your effective cover, since units pre-positioned in AWD can be pulled into FBA faster than ocean freight. For lead time, model the path you actually use for replenishment, not the path you might use.
How often should I recompute my reorder lead time?
Whenever a stage drifts. Common triggers: a new supplier or freight forwarder, a change in mode (air ↔ ocean), a new prep center, peak season congestion (Lunar New Year, Q4 port slowdowns), or Amazon receiving times getting worse at the FC you ship to. Quarterly minimum, monthly if your supply chain is changing.
Should I separate ocean vs air freight in my plan?
Yes — they're effectively different lead times. Many sellers keep two reorder lead time profiles per SKU: a base ocean number for normal replenishment and an expedited air-freight number for stockout-recovery scenarios. Run the calculator twice and save both.
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▲ Profit Hawk

Want this tracked automatically across all your Amazon SKUs?

Profit Hawk watches your real lead times end-to-end — production, freight, customs, prep, ground, and FBA receiving — and feeds them into automated replenishment planning across FBA, AWD, and your 3PL.

Start free trialSee Profit Hawk