Amazon IPI Score 2026: How to Improve It and Why It Matters

What Is the Amazon IPI Score?

The Inventory Performance Index (IPI) is Amazon's composite metric for evaluating how efficiently you manage FBA inventory. Amazon introduced IPI in 2018 to encourage sellers to maintain healthy inventory levels: not too much (driving up storage costs), not too little (creating stockouts).

According to Amazon's IPI documentation, the score updates weekly and is visible in Seller Central under Inventory > Inventory Planning > Performance. Amazon checks your IPI at two evaluation periods: the last 6 weeks of each quarter, with limits applied the following quarter if you're below threshold.

The 4 Factors That Determine Your IPI Score

Amazon doesn't publish the exact IPI formula, but they do reveal the four components. Based on seller testing and Amazon's IPI documentation, here's how they're weighted:

What Happens When Your IPI Falls Below 400

If your IPI drops below 400 during an evaluation period, Amazon enforces storage volume limits for the following quarter. These limits cap the total cubic feet of inventory you can store in FBA, calculated separately for standard-size and oversized items.

7 Strategies to Improve Your IPI Score Fast

IPI improvements compound. Fixing excess inventory also improves sell-through rate. Resolving stranded listings immediately removes dead weight. Here are the strategies ordered by impact speed.

1. Fix Stranded Inventory Immediately (Same-Day Impact)

Go to Inventory > Fix Stranded Inventory in Seller Central. Resolve every stranded listing today. Common fixes: relist the product, match to an existing ASIN, or create a removal order. Stranded inventory has zero revenue potential but counts against your IPI. Fixing it is the fastest IPI boost because it removes dead weight from the calculation.

2. Clear Excess Inventory with Targeted Promotions (1-2 Week Impact)

Amazon flags ASINs as "excess" when holding costs exceed the expected revenue from selling at current velocity. For each excess ASIN, you have three options: run a Lightning Deal, reduce price by 10-20%, or create a removal order. Running a targeted promotion is usually better than removal because you recover some margin and improve sell-through rate simultaneously.

3. Reduce DOI to 45 Days Across Your Catalog (2-4 Week Impact)

Days of Inventory (DOI) is the most practical lever for IPI improvement. If your average DOI is 90 days, you're holding twice as much stock as necessary. Reduce restock quantities to target 45-day supply. This simultaneously reduces excess inventory percentage and improves sell-through rate. Two IPI factors improved with one action.

4. Remove Dead SKUs (Immediate Impact)

Sort your FBA inventory by units sold in the last 90 days. Any SKU with zero or near-zero sales is dragging your IPI down. Create removal orders for truly dead inventory. The removal fee ($1.04-$1.53/unit) is always cheaper than months of storage fees plus the IPI penalty. Use Nova's Winners & Losers analysis to identify which SKUs aren't earning their shelf space.

5. Increase Sell-Through with PPC on Slow Movers (2-3 Week Impact)

For ASINs flagged as excess that still have demand potential, launch a targeted Sponsored Products campaign to accelerate sales velocity. Even a modest increase in daily sales (2-3 extra units) can move an ASIN from "excess" to "healthy" within 2-3 weeks. Track the TACoS impact to ensure the ad spend doesn't exceed the storage fee savings.

6. Maintain 90%+ In-Stock Rate on Top Sellers (Ongoing)

While in-stock rate carries less IPI weight, consistent stockouts on your best sellers still hurt. Set up restock alerts for your top 20 revenue-generating ASINs. Use Nova's pipeline projections to ensure inbound shipments arrive before you hit zero units. The goal is never running out on high-velocity products.

7. Use AWD as a Buffer for Bulk Inventory (Ongoing)

Amazon Warehousing and Distribution (AWD) Stores bulk inventory outside FBA. Units in AWD don't count against your FBA storage volume or IPI calculations. By keeping 60-90 days of stock in AWD and replenishing FBA with 30-day batches, you improve both IPI and storage costs simultaneously. Read our restock limits guide for more on capacity management.

IPI Evaluation Timeline: When Amazon Checks Your Score

Amazon evaluates IPI scores during specific windows each quarter. Understanding this timeline lets you plan inventory actions proactively instead of reacting to limit notifications.

IPI and Storage Fees: The Double Penalty

Low IPI doesn't just limit your storage capacity. It creates a vicious cycle with storage fees:

The key insight: IPI improvement is a flywheel, not a one-time fix. Once you break into the upward spiral, maintaining a high IPI becomes easier because all four factors reinforce each other. The hard part is the initial cleanup. Focus your first two weeks on stranded inventory and dead SKUs (fastest impact), then shift to DOI optimization for sustained improvement.

Further Reading