COMPARISON

Order book vs last price on prediction markets

Last price is a trade print; order-book mid/top reflects resting liquidity. Insydr surfaces both concepts carefully so readers do not confuse sparse prints with deep books.

Last reviewed SEP 10, 2026Updated SEP 10, 2026Reviewer Product

Comparison table

SignalWhat it reflectsFailure modeBetter when
Last priceMost recent fillStale or tiny printsConfirming that a trade happened
Top of bookBest bid/ask restingSpoofing / thin booksShort-horizon quote checks
Depth / imbalanceSize near touchSparse levelsLiquidity / move-cost context
Implied probability (Insydr)Snapshot primary outcomeMissing observation timePublic page citation with timestamp

Why the distinction matters

A last trade can be stale or tiny. Top-of-book and depth summarize resting interest. Mixing them produces misleading “probability” stories.

On Insydr pages

Implied primary probabilities come from the snapshot builder's defined primary outcome. Liquidity methodology pages explain how depth and imbalance are summarized. Always prefer the labeled observation time over screenshots without timestamps.

Practical rule

Use last price to understand what traded; use book metrics to understand what is offered. Do not average them into a single unofficial “true odds” number.

Sources