Enter the number of completed sales found in search filters.
Enter the number of items currently available for sale.
Calculated Sell-Through Rate
0%
Understanding eBay Sell-Through Rate
The eBay Sell-Through Rate (STR) is arguably the most critical metric for resellers, flippers, and e-commerce store owners. It measures the velocity at which an item sells relative to how many are currently available on the market. By calculating STR, you can determine if a product is in high demand or if the market is oversaturated.
How is Sell-Through Rate Calculated?
The formula typically used by eBay sellers compares the number of items sold over a specific period (usually the last 90 days) against the number of active listings currently available.
STR % = (Number of Sold Items / Number of Active Listings) × 100
Interpreting Your Results
Knowing your percentage is only half the battle; knowing what it means for your inventory strategy is key:
Low STR (Under 40%): This indicates a slow-moving market. There is a high supply relative to demand. You may need to price competitively or expect to hold the item for several months.
Average STR (40% – 100%): This is a healthy market. Items generally sell within 1 to 3 months. Pricing near the market average usually results in a sale.
High STR (Over 100%): This indicates very high demand. There are more buyers than sellers. Items in this category often sell within days or weeks, and you can often price at a premium.
Real-World Examples
Imagine you are sourcing video games. You find a specific title and look it up on the eBay app:
Example A (High Demand): You see 200 sold in the last 90 days, but only 50 are currently listed. Calculation: (200 / 50) * 100 = 400% STR. Verdict: Buy it immediately; it will sell very fast.
Example B (Oversaturated): You see 20 sold in the last 90 days, and there are 200 currently listed. Calculation: (20 / 200) * 100 = 10% STR. Verdict: Avoid or price very low, as it will likely sit for a long time.
Why Use the 90-Day Window?
eBay's "Sold" filter generally displays data from the last 90 days. This provides a quarterly view of market performance, smoothing out daily fluctuations while still being recent enough to be relevant. When using this calculator, ensure your "Sold Listings" count corresponds to this 90-day historical data for accuracy.
function calculateSTR() {
// 1. Get input values
var soldInput = document.getElementById("soldListings").value;
var activeInput = document.getElementById("activeListings").value;
var resultDiv = document.getElementById("result");
var strValueDiv = document.getElementById("strValue");
var strAnalysisDiv = document.getElementById("strAnalysis");
var salesVelocityDiv = document.getElementById("salesVelocity");
// 2. Validate inputs
var sold = parseFloat(soldInput);
var active = parseFloat(activeInput);
if (isNaN(sold) || isNaN(active) || sold < 0 || active < 0) {
alert("Please enter valid positive numbers for both sold and active listings.");
resultDiv.style.display = "none";
return;
}
if (active === 0) {
resultDiv.style.display = "block";
strValueDiv.innerHTML = "Infinite";
strAnalysisDiv.className = "analysis-box analysis-good";
strAnalysisDiv.innerHTML = "Unicorn Alert: There are sold listings but ZERO active competition. This is a perfect selling opportunity.";
salesVelocityDiv.innerHTML = "";
return;
}
// 3. Perform Calculation
var str = (sold / active) * 100;
// 4. Display Result
resultDiv.style.display = "block";
strValueDiv.innerHTML = str.toFixed(2) + "%";
// 5. Analysis Logic
var analysisText = "";
var analysisClass = "";
var velocityText = "";
if (str >= 100) {
analysisClass = "analysis-good";
analysisText = "Excellent Demand (Fast Mover): The sell-through rate is over 100%. Demand exceeds supply. Expect this item to sell very quickly (often within days or a couple of weeks) if priced correctly.";
velocityText = "Estimated Sales Pace: Very High Velocity";
} else if (str >= 40) {
analysisClass = "analysis-avg";
analysisText = "Good Demand (Steady Mover): The sell-through rate is between 40% and 100%. This is a healthy market. Expect a sale within 1 to 3 months.";
velocityText = "Estimated Sales Pace: Moderate Velocity";
} else {
analysisClass = "analysis-bad";
analysisText = "Low Demand (Slow Mover): The sell-through rate is under 40%. The market is saturated. Expect this item to sit for several months unless priced aggressively low.";
velocityText = "Estimated Sales Pace: Low Velocity (Long Tail)";
}
strAnalysisDiv.className = "analysis-box " + analysisClass;
strAnalysisDiv.innerHTML = analysisText;
salesVelocityDiv.innerHTML = velocityText;
}