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SLC

Sell-Through Rate Calculator

Calculate sell-through rate, unsold units, and daily velocity for inventory over any time period — the health check for stocking decisions.

Inventory + sales

Sell-through rate

37.5%

Unsold inventory

75

Sales velocity / day

1.50

Projected monthly sales

45

At current pace

Sell-through 37.5% — solid mid-range.

Higher sell-through generally signals healthier inventory. Consistently low rates mean over-buying, pricing issues, or slow SKUs.

All calculations are estimates based on average platform fees. Real profits may vary depending on category, ads, and shipping.

Free worksheet for your next step

Turn this calculator result into a plan with a matching worksheet, checklist, or printable resource.

  • TrackerHandmade

    Handmade Inventory Tracker

    Track materials, finished stock, reorder points, and cost per item across your handmade product line in one simple inventory workbook.

  • PlannerAmazon FBA

    Amazon FBA Inventory Planner

    Plan FBA reorder points, lead times, and stock buffers to avoid stockouts and long-term storage fees.

How to use this calculator

  1. Enter your numbers in each field above — the calculator updates instantly as you type, so there's nothing to submit.
  2. Use your real figures when you have them, or sensible estimates while you're planning. If a field doesn't apply, leave it at zero.
  3. Compare the results, then change one input at a time to see how each lever (price, cost, fees, volume) moves the outcome.

Formula

Sell-through % = Sold ÷ Listed × 100 · Unsold = Listed − Sold · Velocity/day = Sold ÷ Days · Projected monthly = Velocity × 30

Worked example

120 listed, 45 sold in 30 days.

  1. Rate = 45 ÷ 120 = 37.5%
  2. Unsold = 75
  3. Velocity = 1.5/day
  4. Projected monthly = 45

Answer: 37.5% sell-through in 30 days

How it works

Sell-through is the cleanest inventory-health signal. Consistently below 20–30% in a month usually means over-ordering or a pricing problem — not a marketing problem.

How to interpret your results

  • Dollar values are shown per sale, per order, or per item unless a result is explicitly labelled monthly, weekly, or daily.
  • Percentages (margin, ROI, conversion rate) are easier to compare across products and price points than raw dollars — use them when you benchmark.
  • A positive result means you're ahead after the costs and fees you entered. A negative result means the current numbers don't work — change a lever (raise price, cut a cost, lower ad spend) and recalculate.
  • Treat the output as a planning estimate, not a guarantee. Fees, taxes, and conversion rates shift over time — re-run the numbers whenever a key input changes.

Common mistakes

  • Averaging across SKUs and hiding a dead product.
  • Measuring sell-through over too short a window.
  • Ignoring seasonality — Q4 rates aren't Q1 rates.

Go deeper with plain-English guides on the same topic.

FAQ

What's a healthy sell-through rate?
40–60% per month is strong for most physical goods. Under 20% signals overstock or a slow SKU.
How is this different from inventory reorder point?
Sell-through measures how well existing inventory is moving. Reorder point tells you when to restock.

Why trust this calculator?

This tool uses standard mathematical formulas and commonly accepted calculation methods, shown openly in the Formula section above so you can verify the math yourself. Results are estimates based on the information you enter and do not account for every individual circumstance. For important financial, tax, legal, medical, or business decisions, please double-check with a qualified professional before acting on the numbers.

Keep going

One calculator rarely tells the full story. Pair this one with a related tool below to pressure-test your numbers from a different angle, or browse Selling & Business Calculators for more in the same category.

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