⌘K

Arb monitor

We watch negRisk basket arbitrage across Polymarket continuously and surface a riskless edge the instant one appears. Most of the time there are none — here’s the honest live state.

Monitoring / informational · top-of-book · not financial advice.

0
live arbs right now
43
baskets monitored
100.9¢
tightest complete basket
18 / 25
complete / incomplete
95¢$1 = arb threshold105¢
as of 2026-06-18 16:28 UTC

What this monitors

On a negRisk basket (a market with several mutually-exclusive outcomes), the “Yes” asks should sum to about $1. If they ever sum to less than $1, buying one share of every outcome costs under a dollar but pays out exactly $1 — a riskless edge.

In practice the order book almost always prices this out by ~the spread — the tightest complete basket right now sums to 100.9¢, just over $1. That’s expected; a standing sub-$1 basket would be taken instantly. The value here is the continuous watch, not a promise of arbs.

No live arb right now. We’re watching 43 baskets continuously — the moment one prices below $1 it appears here, with its full breakdown.