SimpleFunctions
20 contractsKalshi + Polymarketrefreshed just nowCloses Jun 19, 2026 · 46d2pp · 11h

Bank of Japan Decision in April

Liquidity-weighted aggregate sits at 50% across 20 contracts. Kalshi at 70%, Polymarket at 48% — a 22pp cross-venue gap.

Implied probability

50%
0%50%100%

Kalshi

70%

2 contracts

Polymarket

48%

18 contracts

Cross-venue gap

22pp

wide divergence

24h move

−2pp

11h ago

24h volume

$13K

20 contracts

Closes

Jun 19, 2026

46 days

30-day trend

0%50%100%-30d-3w-2w-1wtodayAggregate: 53% (26 days, 26 points)Aggregate: 53% on 2026-05-03
Aggregate of 20 contracts · 26d

Cross-venue edge

Kalshi 70¢ · Polymarket 48¢ · 22pp spread

Buy on Polymarket (48¢, 18 contracts) and sell on Kalshi (70¢) — assuming both contracts settle on the same outcome.

Bracket families

12 clusters across 20 contracts.

These contracts were grouped by title similarity. The headline aggregate combines all clusters; verify the cluster you actually need before quoting a number.

Heads-up — heterogeneous clusters

The top two clusters share only 20% of their title tokens — “Reserve Bank” vs “Bank of Russia decision in June”. The headline aggregate weights both, so the number on this page is meaningful only if the clusters resolve to the same question.

Cluster 1

Reserve Bank

4 contracts$7K

Cluster 2

Bank of Russia decision in June

2 contracts$2K

Cluster 3

Bank of Mexico Decision in May

2 contracts$2K

Cluster 4

Bank of Japan Decision in June

2 contracts$438

Cluster 5

Bank of Israel Decision in May

2 contracts$251

Cluster 6

Bank of Canada decision in June

2 contracts$104

Cluster 7

Bank of Brazil Decision in June

1 contract$360

Cluster 8

Bank of Korea decision in May

1 contract$263

Cluster 9

Will the Bank of Japan Hike 25bps at the June 2026 Monetary Policy Meeting

1 contract$255

Cluster 10

South African Reserve Bank Decision in May

1 contract$235

Cluster 11

Central Bank of Colombia Decision in June

1 contract$0

Cluster 12

Will the Japan inflation rate MoM for April 2026 be above -0.3%

1 contract$0

Analysis

This probability reflects market expectations for a Bank of Japan interest rate decision occurring in April 2026. At 52%, traders are essentially split between two outcomes, suggesting genuine uncertainty about the central bank's monetary policy stance. The probability is primarily driven by recent economic data from Japan—including inflation trends, employment figures, and GDP growth—which determine whether the BoJ will adjust rates or hold steady. Market participants are also factoring in global monetary policy signals, particularly from other major central banks that influence currency valuations and capital flows. The key catalyst for resolving this uncertainty will be the official BoJ decision announcement on its scheduled meeting date, after which the contract will settle based on the actual policy action taken.

  • Recent Japan CPI and core inflation readings relative to BoJ's 2% target, which directly influences rate decision likelihood
  • Employment and wage growth data showing labor market tightness, a key factor in the BoJ's policy calculus
  • USD/JPY exchange rate movements and expectations for Fed policy divergence, which affect BoJ decision timing
  • Scheduled BoJ Monetary Policy Decision meeting date and any forward guidance statements released beforehand
  • Comparative rate expectations across other G7 central banks, which shape relative attractiveness of yen-denominated assets

What moved the line

  • Apr 29Decrease49pp3180¢ · Polymarket
  • Apr 29No change43pp6522¢ · Polymarket
  • Apr 30Above -0.3%41pp5091¢ · Kalshi
  • Apr 30No change17pp225¢ · Polymarket
  • Apr 30No Change17pp6986¢ · Polymarket

Recently closed in general

These markets stopped trading. Last odds and any captured outcome are shown above — full settlement detail lives at the venue.

More like this

Adjacent prediction questions.

How we compute these odds

SimpleFunctions aggregates live prediction-market contracts from Kalshi and Polymarket. Each slug groups contracts that resolve on the same underlying event, identified by venue event_id.

For binary slugs, the headline probability is the liquidity-weighted mid-price across all bound contracts. For multi-outcome slugs (e.g. elections with 3+ candidates), the headline is the leader’s price; we never arithmetically average disjoint outcomes — that would produce a number with no real-world meaning.

Snapshots refresh every 5 minutes during market hours; daily aggregates are computed at 04:00 UTC. The 30-day sparkline is drawn from per-ticker daily means stored in market_indicator_daily; 24h delta and movement events are derived from the same source.

Last updated on this page: just now.