2028 Republican Nominee Odds for President

LIVE
Updated 59 minutes ago · 10:41 AM PST

Prediction markets have J.D. Vance as the favorite candidate to win the 2028 Republican nominee race, with a 53.0% probability or, -113 odds. Marco Rubio holds second at 13.1% (+663) , while Donald J. Trump sits in third at 3.3% (+2,976). Total volume for Republican Nominee market at Kalshi and Polymarket stands at $2.2M in the last 24 hours with $6.0K on Kalshi and $2.2M on Polymarket. Our odds tracker aggregates live pricing to show consensus probabilities across prediction markets, updated hourly with arbitrage detection.

Largest Spread
3.51%
J.D. Vance → View arbs
Consensus Leader
53.0%
J.D. Vance
24H Volume (Share)
$2.2M
K: 0.3% P: 99.7%
Momentum Leader
—
24H change
Period:
Platform:

Probability Over Time

Hover for details · Cursor-synced tooltips

Tap "Chart settings" to adjust the chart.

Chart settings
Outcome:
Aggregated (VWAP)
Volume
Kalshi
Polymarket
Cross-Venue Spread

Current Odds Snapshot

Current probabilities across platforms with liquidity indicators

Sort:
JDV
J.D. Vance
Vol $36.4K Spread 5.0%
Agg 53.0%
↓ -0.6%
P 53.5%
K 48.5%
Polymarket 53.5%
Vol $32.9K 53–54¢
Kalshi 48.5%
Vol $3.5K 48–49¢
MR
Marco Rubio
Vol $29.6K Spread 2.5%
Agg 13.1%
↓ -0.4%
K 15.5%
P 13.0%
Kalshi 15.5%
Vol $1.7K 15–16¢
Polymarket 13.0%
Vol $27.9K 12.9–13¢
DJT
Donald J. Trump
Vol $54.7K Spread 0.3%
Agg 3.3%
↓ -0.1%
K 3.5%
P 3.3%
Kalshi 3.5%
Vol $282 3–4¢
Polymarket 3.3%
Vol $54.4K 3.2–3.3¢
RD
Ron DeSantis
Vol $1.6K Spread 0.5%
Agg 3.1%
↑ +0.1%
K 3.5%
P 3.1%
Kalshi 3.5%
Vol $65 3–4¢
Polymarket 3.1%
Vol $1.5K 3–3.1¢
TC
Tucker Carlson
Vol $5.6K Spread 0.0%
Agg 2.5%
↑ +0.1%
K 2.5%
P 2.5%
Kalshi 2.5%
Vol $83 2–3¢
Polymarket 2.5%
Vol $5.6K 2.4–2.6¢
TC
Ted Cruz
Vol $15.8K Spread 0.8%
Agg 1.8%
↓ -0.2%
K 2.5%
P 1.8%
Kalshi 2.5%
Vol $2 2–3¢
Polymarket 1.8%
Vol $15.8K 1.7–1.8¢
DTJ
Donald Trump Jr.
Vol $8.3K Spread 0.9%
Agg 1.7%
— +0.0%
K 2.5%
P 1.7%
Kalshi 2.5%
Vol $149 2–3¢
Polymarket 1.7%
Vol $8.2K 1.6–1.7¢
MTG
Marjorie Taylor Greene
Vol $7.8K Spread 2.0%
Agg 1.6%
— +0.0%
K 3.5%
P 1.6%
Kalshi 3.5%
Vol $69 3–4¢
Polymarket 1.6%
Vol $7.8K 1.5–1.6¢
TM
Thomas Massie
Vol $4 Spread —
Agg 1.5%
— +0.0%
K 1.5%
Kalshi 1.5%
Vol $4 1–2¢
VR
Vivek Ramaswamy
Vol $432.0K Spread 0.0%
Agg 1.5%
↑ +0.4%
K 1.5%
P 1.5%
Kalshi 1.5%
Vol $6 1–2¢
Polymarket 1.5%
Vol $432.0K 1.4–1.5¢
GY
Glenn Youngkin
Vol $3.9K Spread 1.2%
Agg 1.4%
— +0.0%
K 2.5%
P 1.4%
Kalshi 2.5%
Vol $14 2–3¢
Polymarket 1.4%
Vol $3.9K 1.3–1.4¢
NH
Nikki Haley
Vol $7.0K Spread 0.4%
Agg 1.2%
— +0.0%
K 1.5%
P 1.2%
Kalshi 1.5%
Vol $18 1–2¢
Polymarket 1.2%
Vol $7.0K 1.1–1.2¢
BK
Brian Kemp
Vol $20.7K Spread 0.4%
Agg 1.1%
↑ +0.1%
K 1.5%
P 1.1%
Kalshi 1.5%
Vol $0 1–2¢
Polymarket 1.1%
Vol $20.7K 1–1.1¢
IT
Ivanka Trump
Vol $1.5K Spread —
Agg 1.1%
↓ -0.1%
P 1.1%
Polymarket 1.1%
Vol $1.5K 1–1.1¢
RFK
Robert F. Kennedy Jr.
Vol $65.4K Spread 0.6%
Agg 0.9%
— +0.0%
K 1.5%
P 0.9%
Kalshi 1.5%
Vol $1 1–2¢
Polymarket 0.9%
Vol $65.4K 0.8–0.9¢
TG
Tulsi Gabbard
Vol $5.7K Spread 1.8%
Agg 0.8%
— +0.0%
K 2.5%
P 0.8%
Kalshi 2.5%
Vol $1 2–3¢
Polymarket 0.8%
Vol $5.7K 0.7–0.8¢
JH
Josh Hawley
Vol $39.6K Spread 0.8%
Agg 0.8%
— +0.0%
K 1.5%
P 0.8%
Kalshi 1.5%
Vol $1 1–2¢
Polymarket 0.8%
Vol $39.6K 0.7–0.8¢
RP
Rand Paul
Vol $92.2K Spread —
Agg 0.8%
— +0.0%
P 0.8%
Polymarket 0.8%
Vol $92.2K 0.7–0.8¢
SB
Steve Bannon
Vol $46.9K Spread 0.9%
Agg 0.7%
— +0.0%
K 1.5%
P 0.7%
Kalshi 1.5%
Vol $1 1–2¢
Polymarket 0.7%
Vol $46.9K 0.6–0.7¢
GA
Greg Abbott
Vol $10.9K Spread 0.9%
Agg 0.7%
— +0.0%
K 1.5%
P 0.7%
Kalshi 1.5%
Vol $0 1–2¢
Polymarket 0.7%
Vol $10.9K 0.6–0.7¢
KK
Kim Kardashian
Vol $213.5K Spread —
Agg 0.7%
↓ -0.1%
P 0.7%
Polymarket 0.7%
Vol $213.5K 0.6–0.7¢
EK
Erika Kirk
Vol $11.0K Spread 0.1%
Agg 0.6%
— +0.0%
P 0.7%
K 0.5%
Polymarket 0.7%
Vol $11.0K 0.6–0.7¢
Kalshi 0.5%
Vol $4 0–1¢
SHS
Sarah Huckabee Sanders
Vol $183.5K Spread 1.0%
Agg 0.5%
— +0.0%
K 1.5%
P 0.5%
Kalshi 1.5%
Vol $0 1–2¢
Polymarket 0.5%
Vol $183.5K 0.5–0.6¢
MG
Matt Gaetz
Vol $54.5K Spread 0.0%
Agg 0.5%
— +0.0%
P 0.5%
K 0.5%
Polymarket 0.5%
Vol $54.5K 0.5–0.6¢
Kalshi 0.5%
Vol $0 0–1¢
EM
Elon Musk
Vol $23.1K Spread 0.0%
Agg 0.5%
— +0.0%
P 0.5%
K 0.5%
Polymarket 0.5%
Vol $23.0K 0.5–0.6¢
Kalshi 0.5%
Vol $23 0–1¢
MP
Mike Pence
Vol $56.5K Spread 0.1%
Agg 0.4%
— +0.0%
K 0.5%
P 0.4%
Kalshi 0.5%
Vol $0 0–1¢
Polymarket 0.4%
Vol $56.5K 0.4–0.5¢
KN
Kristi Noem
Vol $133.9K Spread 0.1%
Agg 0.4%
— +0.0%
K 0.5%
P 0.4%
Kalshi 0.5%
Vol $0 0–1¢
Polymarket 0.4%
Vol $133.9K 0.4–0.5¢
KB
Katie Britt
Vol $321.7K Spread 0.1%
Agg 0.4%
— +0.0%
K 0.5%
P 0.4%
Kalshi 0.5%
Vol $0 0–1¢
Polymarket 0.4%
Vol $321.7K 0.4–0.5¢
JT
John Thune
Vol $29.6K Spread 0.1%
Agg 0.4%
— +0.0%
K 0.5%
P 0.4%
Kalshi 0.5%
Vol $0 0–1¢
Polymarket 0.4%
Vol $29.6K 0.4–0.5¢
ES
Elise Stefanik
Vol $131.6K Spread 0.1%
Agg 0.4%
— +0.0%
K 0.5%
P 0.4%
Kalshi 0.5%
Vol $0 0–1¢
Polymarket 0.4%
Vol $131.6K 0.4–0.5¢
BD
Byron Donalds
Vol $132.0K Spread 1.0%
Agg 0.4%
— +0.0%
K 1.5%
P 0.4%
Kalshi 1.5%
Vol $1 1–2¢
Polymarket 0.4%
Vol $132.0K 0.4–0.5¢
TB
Tom Brady
Vol $25.6K Spread —
Agg 0.4%
— +0.0%
P 0.4%
Polymarket 0.4%
Vol $25.6K 0.4–0.5¢
OutcomeAggregatedSpreadVolumeKalshiPolymarket
JDV
J.D. Vance
53.0%
↓ -0.6%
5.0%
$36.4K
Kalshi 48.5%
48–49¢ Vol $3.5K
Polymarket 53.5%
53–54¢ Vol $32.9K
MR
Marco Rubio
13.1%
↓ -0.4%
2.5%
$29.6K
Kalshi 15.5%
15–16¢ Vol $1.7K
Polymarket 13.0%
12.9–13¢ Vol $27.9K
DJT
Donald J. Trump
3.3%
↓ -0.1%
0.3%
$54.7K
Kalshi 3.5%
3–4¢ Vol $282
Polymarket 3.3%
3.2–3.3¢ Vol $54.4K
RD
Ron DeSantis
3.1%
↑ +0.1%
0.5%
$1.6K
Kalshi 3.5%
3–4¢ Vol $65
Polymarket 3.1%
3–3.1¢ Vol $1.5K
TC
Tucker Carlson
2.5%
↑ +0.1%
0.0%
$5.6K
Kalshi 2.5%
2–3¢ Vol $83
Polymarket 2.5%
2.4–2.6¢ Vol $5.6K
TC
Ted Cruz
1.8%
↓ -0.2%
0.8%
$15.8K
Kalshi 2.5%
2–3¢ Vol $2
Polymarket 1.8%
1.7–1.8¢ Vol $15.8K
DTJ
Donald Trump Jr.
1.7%
— +0.0%
0.9%
$8.3K
Kalshi 2.5%
2–3¢ Vol $149
Polymarket 1.7%
1.6–1.7¢ Vol $8.2K
MTG
Marjorie Taylor Greene
1.6%
— +0.0%
2.0%
$7.8K
Kalshi 3.5%
3–4¢ Vol $69
Polymarket 1.6%
1.5–1.6¢ Vol $7.8K
TM
Thomas Massie
1.5%
— +0.0%
—
$4
Kalshi 1.5%
1–2¢ Vol $4
Polymarket —
— Vol $0
VR
Vivek Ramaswamy
1.5%
↑ +0.4%
0.0%
$432.0K
Kalshi 1.5%
1–2¢ Vol $6
Polymarket 1.5%
1.4–1.5¢ Vol $432.0K
GY
Glenn Youngkin
1.4%
— +0.0%
1.2%
$3.9K
Kalshi 2.5%
2–3¢ Vol $14
Polymarket 1.4%
1.3–1.4¢ Vol $3.9K
NH
Nikki Haley
1.2%
— +0.0%
0.4%
$7.0K
Kalshi 1.5%
1–2¢ Vol $18
Polymarket 1.2%
1.1–1.2¢ Vol $7.0K
BK
Brian Kemp
1.1%
↑ +0.1%
0.4%
$20.7K
Kalshi 1.5%
1–2¢ Vol $0
Polymarket 1.1%
1–1.1¢ Vol $20.7K
IT
Ivanka Trump
1.1%
↓ -0.1%
—
$1.5K
Kalshi —
— Vol $0
Polymarket 1.1%
1–1.1¢ Vol $1.5K
RFK
Robert F. Kennedy Jr.
0.9%
— +0.0%
0.6%
$65.4K
Kalshi 1.5%
1–2¢ Vol $1
Polymarket 0.9%
0.8–0.9¢ Vol $65.4K
TG
Tulsi Gabbard
0.8%
— +0.0%
1.8%
$5.7K
Kalshi 2.5%
2–3¢ Vol $1
Polymarket 0.8%
0.7–0.8¢ Vol $5.7K
JH
Josh Hawley
0.8%
— +0.0%
0.8%
$39.6K
Kalshi 1.5%
1–2¢ Vol $1
Polymarket 0.8%
0.7–0.8¢ Vol $39.6K
RP
Rand Paul
0.8%
— +0.0%
—
$92.2K
Kalshi —
— Vol $0
Polymarket 0.8%
0.7–0.8¢ Vol $92.2K
SB
Steve Bannon
0.7%
— +0.0%
0.9%
$46.9K
Kalshi 1.5%
1–2¢ Vol $1
Polymarket 0.7%
0.6–0.7¢ Vol $46.9K
GA
Greg Abbott
0.7%
— +0.0%
0.9%
$10.9K
Kalshi 1.5%
1–2¢ Vol $0
Polymarket 0.7%
0.6–0.7¢ Vol $10.9K
KK
Kim Kardashian
0.7%
↓ -0.1%
—
$213.5K
Kalshi —
— Vol $0
Polymarket 0.7%
0.6–0.7¢ Vol $213.5K
EK
Erika Kirk
0.6%
— +0.0%
0.1%
$11.0K
Kalshi 0.5%
0–1¢ Vol $4
Polymarket 0.7%
0.6–0.7¢ Vol $11.0K
SHS
Sarah Huckabee Sanders
0.5%
— +0.0%
1.0%
$183.5K
Kalshi 1.5%
1–2¢ Vol $0
Polymarket 0.5%
0.5–0.6¢ Vol $183.5K
MG
Matt Gaetz
0.5%
— +0.0%
0.0%
$54.5K
Kalshi 0.5%
0–1¢ Vol $0
Polymarket 0.5%
0.5–0.6¢ Vol $54.5K
EM
Elon Musk
0.5%
— +0.0%
0.0%
$23.1K
Kalshi 0.5%
0–1¢ Vol $23
Polymarket 0.5%
0.5–0.6¢ Vol $23.0K
MP
Mike Pence
0.4%
— +0.0%
0.1%
$56.5K
Kalshi 0.5%
0–1¢ Vol $0
Polymarket 0.4%
0.4–0.5¢ Vol $56.5K
KN
Kristi Noem
0.4%
— +0.0%
0.1%
$133.9K
Kalshi 0.5%
0–1¢ Vol $0
Polymarket 0.4%
0.4–0.5¢ Vol $133.9K
KB
Katie Britt
0.4%
— +0.0%
0.1%
$321.7K
Kalshi 0.5%
0–1¢ Vol $0
Polymarket 0.4%
0.4–0.5¢ Vol $321.7K
JT
John Thune
0.4%
— +0.0%
0.1%
$29.6K
Kalshi 0.5%
0–1¢ Vol $0
Polymarket 0.4%
0.4–0.5¢ Vol $29.6K
ES
Elise Stefanik
0.4%
— +0.0%
0.1%
$131.6K
Kalshi 0.5%
0–1¢ Vol $0
Polymarket 0.4%
0.4–0.5¢ Vol $131.6K
BD
Byron Donalds
0.4%
— +0.0%
1.0%
$132.0K
Kalshi 1.5%
1–2¢ Vol $1
Polymarket 0.4%
0.4–0.5¢ Vol $132.0K
TB
Tom Brady
0.4%
— +0.0%
—
$25.6K
Kalshi —
— Vol $0
Polymarket 0.4%
0.4–0.5¢ Vol $25.6K

Arbitrage Scanner

Current cross-venue opportunities with fee calculations

Pairs (Venue-to-Venue)

Minimum Spread 1.5%
OutcomeVenue PairLeg A (Buy)Leg B (Sell)Gross SpreadAfter FeesActionableQuick Links
JDV
J.D. Vance
Kalshi → Polymarket
Buy @ K
49¢
Sell @ P
53¢
+4.00%
+3.51%
Yes
MR
Marco Rubio
Polymarket → Kalshi
Buy @ P
13¢
Sell @ K
15¢
+2.00%
+1.85%
Yes
MTG
Marjorie Taylor Greene
Polymarket → Kalshi
Buy @ P
1.6¢
Sell @ K
3¢
+1.40%
+1.33%
No
TG
Tulsi Gabbard
Polymarket → Kalshi
Buy @ P
0.8¢
Sell @ K
2¢
+1.20%
+1.13%
No
GY
Glenn Youngkin
Polymarket → Kalshi
Buy @ P
1.4¢
Sell @ K
2¢
+0.60%
+0.53%
No
BD
Byron Donalds
Polymarket → Kalshi
Buy @ P
0.5¢
Sell @ K
1¢
+0.50%
+0.43%
No
SHS
Sarah Huckabee Sanders
Polymarket → Kalshi
Buy @ P
0.6¢
Sell @ K
1¢
+0.40%
+0.33%
No
SB
Steve Bannon
Polymarket → Kalshi
Buy @ P
0.7¢
Sell @ K
1¢
+0.30%
+0.23%
No
GA
Greg Abbott
Polymarket → Kalshi
Buy @ P
0.7¢
Sell @ K
1¢
+0.30%
+0.23%
No
DTJ
Donald Trump Jr.
Polymarket → Kalshi
Buy @ P
1.7¢
Sell @ K
2¢
+0.30%
+0.23%
No
TC
Ted Cruz
Polymarket → Kalshi
Buy @ P
1.8¢
Sell @ K
2¢
+0.20%
+0.13%
No
JH
Josh Hawley
Polymarket → Kalshi
Buy @ P
0.8¢
Sell @ K
1¢
+0.20%
+0.13%
No
RFK
Robert F. Kennedy Jr.
Polymarket → Kalshi
Buy @ P
0.9¢
Sell @ K
1¢
+0.10%
+0.03%
No
BK
Brian Kemp
Polymarket → Kalshi
Buy @ P
1.1¢
Sell @ K
1¢
-0.10%
-0.17%
No
RD
Ron DeSantis
Polymarket → Kalshi
Buy @ P
3.1¢
Sell @ K
3¢
-0.10%
-0.17%
No
NH
Nikki Haley
Polymarket → Kalshi
Buy @ P
1.2¢
Sell @ K
1¢
-0.20%
-0.27%
No
DJT
Donald J. Trump
Polymarket → Kalshi
Buy @ P
3.3¢
Sell @ K
3¢
-0.30%
-0.37%
No
EK
Erika Kirk
Kalshi → Polymarket
Buy @ K
1¢
Sell @ P
0.6¢
-0.40%
-0.47%
No
VR
Vivek Ramaswamy
Polymarket → Kalshi
Buy @ P
1.5¢
Sell @ K
1¢
-0.50%
-0.57%
No
MG
Matt Gaetz
Kalshi → Polymarket
Buy @ K
1¢
Sell @ P
0.5¢
-0.50%
-0.57%
No
EM
Elon Musk
Kalshi → Polymarket
Buy @ K
1¢
Sell @ P
0.5¢
-0.50%
-0.57%
No
MP
Mike Pence
Polymarket → Kalshi
Buy @ P
0.5¢
Sell @ K
0¢
-0.50%
-0.50%
No
KN
Kristi Noem
Polymarket → Kalshi
Buy @ P
0.5¢
Sell @ K
0¢
-0.50%
-0.50%
No
KB
Katie Britt
Polymarket → Kalshi
Buy @ P
0.5¢
Sell @ K
0¢
-0.50%
-0.50%
No
JT
John Thune
Polymarket → Kalshi
Buy @ P
0.5¢
Sell @ K
0¢
-0.50%
-0.50%
No
ES
Elise Stefanik
Polymarket → Kalshi
Buy @ P
0.5¢
Sell @ K
0¢
-0.50%
-0.50%
No
TC
Tucker Carlson
Kalshi → Polymarket
Buy @ K
3¢
Sell @ P
2.4¢
-0.60%
-0.67%
No

Outcome Diff

Outcome AOutcome BVenueA OddsB OddsDiffStrategyQuick Link
JDV
J.D. Vance
GY
Glenn Youngkin
Polymarket
A
53.50%
B
1.35%
+52.15%
Buy spread
JDV
J.D. Vance
VR
Vivek Ramaswamy
Polymarket
A
53.50%
B
1.45%
+52.05%
Buy spread
JDV
J.D. Vance
MTG
Marjorie Taylor Greene
Polymarket
A
53.50%
B
1.55%
+51.95%
Buy spread
JDV
J.D. Vance
DTJ
Donald Trump Jr.
Polymarket
A
53.50%
B
1.65%
+51.85%
Buy spread
JDV
J.D. Vance
TC
Ted Cruz
Polymarket
A
53.50%
B
1.75%
+51.75%
Buy spread
JDV
J.D. Vance
TC
Tucker Carlson
Polymarket
A
53.50%
B
2.50%
+51.00%
Buy spread
JDV
J.D. Vance
RD
Ron DeSantis
Polymarket
A
53.50%
B
3.05%
+50.45%
Buy spread
JDV
J.D. Vance
DJT
Donald J. Trump
Polymarket
A
53.50%
B
3.25%
+50.25%
Buy spread
JDV
J.D. Vance
TC
Tucker Carlson
Kalshi
A
48.50%
B
2.50%
+46.00%
Buy spread
JDV
J.D. Vance
TC
Ted Cruz
Kalshi
A
48.50%
B
2.50%
+46.00%
Buy spread
JDV
J.D. Vance
DTJ
Donald Trump Jr.
Kalshi
A
48.50%
B
2.50%
+46.00%
Buy spread
JDV
J.D. Vance
GY
Glenn Youngkin
Kalshi
A
48.50%
B
2.50%
+46.00%
Buy spread
JDV
J.D. Vance
TG
Tulsi Gabbard
Kalshi
A
48.50%
B
2.50%
+46.00%
Buy spread
JDV
J.D. Vance
DJT
Donald J. Trump
Kalshi
A
48.50%
B
3.50%
+45.00%
Buy spread
JDV
J.D. Vance
RD
Ron DeSantis
Kalshi
A
48.50%
B
3.50%
+45.00%
Buy spread
JDV
J.D. Vance
MTG
Marjorie Taylor Greene
Kalshi
A
48.50%
B
3.50%
+45.00%
Buy spread
JDV
J.D. Vance
MR
Marco Rubio
Polymarket
A
53.50%
B
12.95%
+40.55%
Buy spread
JDV
J.D. Vance
MR
Marco Rubio
Kalshi
A
48.50%
B
15.50%
+33.00%
Buy spread
MR
Marco Rubio
TC
Tucker Carlson
Kalshi
A
15.50%
B
2.50%
+13.00%
Buy spread
MR
Marco Rubio
TC
Ted Cruz
Kalshi
A
15.50%
B
2.50%
+13.00%
Buy spread
MR
Marco Rubio
DTJ
Donald Trump Jr.
Kalshi
A
15.50%
B
2.50%
+13.00%
Buy spread
MR
Marco Rubio
GY
Glenn Youngkin
Kalshi
A
15.50%
B
2.50%
+13.00%
Buy spread
MR
Marco Rubio
TG
Tulsi Gabbard
Kalshi
A
15.50%
B
2.50%
+13.00%
Buy spread
MR
Marco Rubio
DJT
Donald J. Trump
Kalshi
A
15.50%
B
3.50%
+12.00%
Buy spread
MR
Marco Rubio
RD
Ron DeSantis
Kalshi
A
15.50%
B
3.50%
+12.00%
Buy spread
MR
Marco Rubio
MTG
Marjorie Taylor Greene
Kalshi
A
15.50%
B
3.50%
+12.00%
Buy spread
MR
Marco Rubio
GY
Glenn Youngkin
Polymarket
A
12.95%
B
1.35%
+11.60%
Buy spread
MR
Marco Rubio
VR
Vivek Ramaswamy
Polymarket
A
12.95%
B
1.45%
+11.50%
Buy spread
MR
Marco Rubio
MTG
Marjorie Taylor Greene
Polymarket
A
12.95%
B
1.55%
+11.40%
Buy spread
MR
Marco Rubio
DTJ
Donald Trump Jr.
Polymarket
A
12.95%
B
1.65%
+11.30%
Buy spread
Kalshi Trading Fee 1% (min $0.07, max $1.75) per side
Polymarket Trading Fee 0% (gas only)
Gemini Trading Fee 0.40% per side

After-fee spreads apply the configured taker-fee model per side. Depth/slippage is not modeled in this scanner.

Methodology & Data Mapping

How we aggregate, normalize, and map cross-platform data

Aggregation Method

Default: Volume-Weighted Average Price (VWAP)

Weights each mapped market by its reported 24H USD volume at snapshot time. If volume is unavailable, we fall back to a simple average for that snapshot.

Use the VWAP/Simple toggle above the chart to switch aggregation views.

Data Sources & Cadence

Kalshi: Official API (best bid/ask + last + 24H volume/liquidity when available).

Polymarket: Market data via their API (token prices + best bid/ask + 24H volume/liquidity when available).

Gemini: Public Prediction Markets + ticker endpoints (best bid/ask + last + 24H USD volume when available).

Event data is updated hourly. Older history is downsampled.

Outcome Mapping

Each event links one or more markets per provider. We normalize labels, map provider outcomes into a shared outcome list, and merge mapped markets where appropriate.

Spread & Liquidity

Cross-venue spread: Max–min difference across available venue probabilities for the same outcome.

Liquidity: Relative per-venue indicators based on provider liquidity fields (no depth/slippage modeling).

Arbitrage: Computed from best bid/ask when available (otherwise mid); after-fee spread applies the configured fee model only.