Append sportsbook-style odds next to prediction market prices (Decimal, American, Fractional) with optional fee adjustment.
Users
308
+65 in 30 days
Rating
5.0 / 5
unchanged in 30 days
Ratings
1
0 in 30 days
Store rank
#53K
#45K among extensions
Version
1.2.0
updated 6 Oct 2025
Users
monthly, 13 months
Latest, 16 Oct 2026:308 usersMove the mouse over the chart for any month
Ratings count
monthly, 13 months
Latest, 16 Oct 2026:1 ratingsMove the mouse over the chart for any month
The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.
About Prediction Market to Sports Odds Converter
Chrome extension that appends sportsbook-style odds next to prediction market prices on Polymarket and Kalshi. Shows Decimal, American, and Fractional. Optional fee adjustment (in percentage points) to model effective probability before conversion.
- Finds text like `55%` or `$0.55` and computes:
- Decimal: 1 / p
- American: if p >= 0.5 → -(p/(1-p))*100, else ((1-p)/p)*100
- Fractional: (1 - p) / p as a simplified fraction (approx.)
- Works on SPA updates using a `MutationObserver`.
- Avoids duplicate badges via a data-attribute.
Growth
Window
Users
Change
Ratings
Rating
7 days
+3
+1.0%
0
0.00
30 days
+65
+26.7%
0
0.00
6 months
+257
+503.9%
+1
+5.00
1 year
+306
+15300.0%
+1
+5.00
Chrome Web Store search rankings
Where Prediction Market to Sports Odds Converter appears when people search the store, with the 30 day change