Fed Funds Futures to Probability Calculator: Rate Hike and Cut Odds for the Next FOMC Meeting

A fed funds futures contract settles on the month's average effective fed funds rate, so its price (100 minus that average) tells you what traders expect the rate to be after a meeting. Back out the post-meeting rate from the days before and after the decision, and the share of a 25 bps step it covers is the market's probability of a move. Example: at a 4.00% rate before a meeting on day 28 of a 31-day month, a price of 95.985 implies 4.155% after it, a change of +15.5 bps, or about 62% odds of a 25 bps hike.

Polymarket right now for the October 27–28, 2026 meeting: hike 25 bps 65.5%, no change 33.5% (implied change +16.5 bps) — every meeting on Fed rate odds by meeting.

Fed funds futures to probability calculator

Futures price for the meeting month (e.g. 95.985) Effective fed funds rate before the meeting, % (example value — use today's) Days of the month before the new rate applies Days in the month

Implied rate after the meeting—

Implied change—

Chance of a 25 bps move—

Chance of a 50 bps move—

The inputs above are an example, not today's market: take the current futures price from your broker or exchange. When the meeting falls late in the month few days carry the new rate, so the next month's contract is often a cleaner read.

How the calculation works

The contract pays on the average rate over the whole month. If the rate is r_pre for the first m days and r_post for the remaining N − m days, the average is (m·r_pre + (N − m)·r_post) / N. The calculator solves that for r_post, then reads the change as a mix of 25 bps steps: +12.5 bps is a 50% chance of a 25 bps hike, +37.5 bps is certain 25 plus 50% odds of 50. It ignores the small premium futures can carry, so treat the result as a rough market reading.

Polymarket prices each meeting directly — cut, no change or hike — so you can compare the two readings side by side on Fed rate odds by meeting, which also shows Kalshi's prices.

Try it on live markets

Put real prices into the calculator: every page below shows current odds, 24-hour moves and the market rules.

Frequently asked questions

How do you turn fed funds futures into rate-hike odds?

Take 100 minus the futures price to get the expected average rate for the month, solve for the rate after the meeting using the days before and after the decision, and divide the implied change by 25 bps. +15 bps, for example, is about a 60% chance of a 25 bps hike.

Why use the day-weighted average?

The contract settles on the average effective rate over the whole month, so a decision late in the month only moves a few days of it.

How is this different from Polymarket's Fed odds?

Futures give an expected rate that has to be translated into odds; Polymarket trades each outcome of a meeting directly, so its prices are already probabilities. The two usually agree on the favourite.