---
title: "Amazon FBA Reorder Point Calculator | Your Next 3 Purchase Orders - Flapen"
canonical_url: "https://flapen.com/tools/reorder-point-calculator"
last_updated: "2026-07-18T11:20:44.251Z"
meta:
  description: "Free FBA reorder point calculator — see when to place your next three purchase orders, how many units each needs with MOQ and case packs, and the day you'd stock out if you wait."
  "og:description": "Free FBA reorder point calculator — see when to place your next three purchase orders, how many units each needs with MOQ and case packs, and the day you'd stock out if you wait."
  "og:title": "Amazon FBA Reorder Point Calculator | Your Next 3 Purchase Orders - Flapen"
---

# **FBA Reorder Point Calculator**

When to reorder, how many units, and your next three POs

**Order next by**

**On track**

**—**

in 26 days — order 504 units

**If you don't order**

**—**

stockout in 92 days

** **

—

**Today**

550 units on hand

** **

—

**PO #1**

Order 504 units

** **

—

**PO #1 lands**

630 units on hand

** **

—

**PO #2**

Order 504 units

** **

—

**PO #3**

Order 504 units

**Inventory projection**Projected stockIf you don't orderReorder pointSafety stock**Why —?** 550 units on hand ≈ 92 days of cover 45-day lead time + 21-day safety buffer = order while 396 units (≈ 66 days) remain 92 − 66 ≈ 26 days from today — place PO #1 by —**Your next 3 purchase orders**| **PO** | **Place by** | **Units** | **Cases** | **Est. cost** | **Lands** | **Stock when it lands** |
| --- | --- | --- | --- | --- | --- | --- | | **#1** | — | **504** | 21 | $3,276 | — | 126safety floor | | **#2** | — | **504** | 21 | $3,276 | — | 126safety floor | | **#3** | — | **504** | 21 | $3,276 | — | 126safety floor | Each PO = 60 days of sales (360 units) raised to your 500-unit MOQ, rounded to 21 case packs of 24. ## **How the restock math works — and what actually sets your order date**- **The reorder point** Your reorder point is the stock level that still covers demand across your lead time plus your safety buffer. When fulfillable inventory crosses it, an order placed today lands exactly as you touch safety stock — later than that and you're gambling on the carrier. - **Safety stock is time, not units** Thinking in days keeps the buffer honest as sales change: 21 days of safety stock is 126 units at 6 sales a day but 252 at 12. The calculator converts your day setting to units at your current velocity, so the floor moves with demand. - **Lead time is door to shelf** Count every day between placing the PO and units becoming fulfillable: production, freight, customs, and Amazon check-in. Sellers who only count the factory quote reorder weeks late — measure your slowest recent order, not your fastest. - **Trend changes everything** Growing 20% a month means demand over your lead time is higher than last month's sales suggest — the calculator compounds your trend into every window, pulling order dates earlier as you grow and pushing them out as demand cools. - **MOQ and case packs set real quantities** Suppliers sell minimums and full cases, not spreadsheet-perfect quantities. Each planned PO covers your chosen days of demand, gets raised to the MOQ if needed, then rounds up to whole case packs — a number you can actually put on a purchase order. - **Three orders ahead** One reorder date tells you what to do this week; three tell you your cash calendar for the next two quarters. Because each PO's size fixes when the next one is due, the calculator plans the chain — so you see overlapping orders coming before they collide. ## **Reorder points, safety stock & restock timing**