What's a "good" sell-through rate?

Sell-through rate is the percentage of recent listings that actually sold. It’s the most important number in resale, and the one most resellers ignore.

Here’s how to read it.

The math

eBay’s Finding API returns the last N completed listings for any search. Sell-through is:

sell_through = sold_count / (sold_count + unsold_count)

Run a query for “Carhartt Detroit Jacket Medium” — get back 100 completed listings. 73 sold, 27 didn’t. Sell-through is 73%. That’s a strong signal: this product moves.

What’s “good”

Sell-through	Read this as
80%+	Print money. Buy unless cost basis kills the margin
70–80%	Strong. Confident buy at the right price
50–70%	Okay. Buy if margin is good, expect 2–3 weeks listed
30–50%	Risky. Buy only at fire-sale cost basis
<30%	Walk. The market doesn’t want this

These are rules of thumb across categories. Fashion runs higher (60–80% common); collectibles run lower (30–50% common, but margins compensate).

Why most resellers get this wrong

The trap: you scan an item, see “average sold price $89” and think “great.” But the average is skewed by the listings that actually sold. The unsold ones — the real signal that buyers don’t want this — get hidden if you only look at sold-price averages.

Smart Buy Score weights sell-through heavily for exactly this reason. A high price doesn’t matter if nobody pays it.

What to do at the rack

Three checks:

1. Sell-through ≥ 70%? Buy at any reasonable price.
2. Sell-through 50–70%? Calculate net margin first. If margin clears 60%, buy.
3. Sell-through < 50%? Pass. Find something else.

Memorize the 70% line. It’s the difference between profitable resellers and people who fill garages with unsold inventory.

— Evan