A sneaker price index turns thousands of individual resale prices into a single, trackable number — the same way the S&P 500 summarizes the stock market. SneakPrice publishes the SneakPrice Indexes (the SPX-* family), each a weighted basket of sneakers, refreshed hourly from live eBay market data.
Every SneakPrice index uses one formula: Index = Σ(Price × Weight) ÷ Σ(Weight). Each constituent sneaker contributes its current median resale price, weighted equally in v1. As prices move, the index level moves with them — so a rising SPX-JORDAN means Jordan retros are appreciating as a group, not just one pair.
The benchmark: SPX-RETRO
SPX-RETRO is The SneakPrice Index — a canonical basket of retros (AJ1, AJ3, AJ4, AJ11, Dunk Low, Air Force 1, Samba, Gazelle, NB 990) that everything else trades against. Brand cuts like SPX-NIKE and price-band indexes like SPX-UNDER200 let you isolate a segment.
Why track an index instead of one shoe
Single-pair prices are noisy — one lucky sale can swing a number. An index smooths that noise and reveals the trend of a whole segment, which is what resellers and investors actually need to time entries and exits.
Frequently asked questions
What is a sneaker price index?
A sneaker price index is a single number representing the weighted average resale price of a basket of sneakers, so you can track a whole segment of the market at once instead of one pair.
How often does the sneaker price index update?
SneakPrice index levels are recomputed hourly from live eBay market data.
How is each index calculated?
Index = Σ(Price × Weight) ÷ Σ(Weight). Each constituent sneaker contributes its current median resale price, weighted equally in the current version.
What is SPX-RETRO?
SPX-RETRO is the benchmark index — a canonical basket of retro sneakers known as The SneakPrice Index, which the other SneakPrice Indexes trade against.