A tradable universe is the subset of instruments that you can realistically trade at a given time under your constraints. It is typically narrower than a general research universe because it applies practical filters such as liquidity, market access, minimum order size, and operational restrictions. The tradable universe is often time-varying because liquidity and instrument status change.
Common tradability criteria include minimum recent volume or trade count, maximum spread, minimum order book depth, and reliable data coverage for the data type you use. Some workflows also include operational constraints like supported venues, allowed instrument types, and position limits. Many teams compute tradability using trailing windows (for example, last 24 hours) to avoid lookahead.
A universe is any defined set of instruments for analysis, which may include illiquid or rarely traded symbols. A tradable universe is a stricter subset that aims to reflect instruments you could actually execute on. The tradable universe typically enforces liquidity, spread, depth, and operational constraints.
Compute tradability metrics using trailing windows that end at the decision time (for example, last 24 hours volume as of t). Avoid labeling instruments as tradable based on information that occurs after t. Store the resulting membership as a point-in-time snapshot so you can reproduce it.
Trade counts and volumes indicate activity, quotes indicate spread and update frequency, and order books indicate depth and resilience. Coverage windows help ensure those fields actually exist for the time period you’re evaluating. Using a combination of these gives a more robust tradability definition than relying on a single metric.
You model a market-making strategy across “all spot pairs” on an exchange. Many pairs have quotes only sporadically and order books that disappear for minutes, making it impossible to maintain consistent quoting. By restricting to a tradable universe (for example, pairs with continuous quotes and minimum depth), your simulation better matches what could be executed.
CoinAPI’s trades, quotes, and order book data can support tradable-universe filters such as minimum activity and minimum depth. Combine these with symbol metadata and coverage timestamps to ensure you only include symbols with sufficient data availability in the period you test. This improves the realism of execution and liquidity assumptions.