📊 Data Study · Kalshi BTC 15-Minute Markets

What 9,800 Graded Kalshi BTC 15-Minute Windows Show About a Coin Flip

DegenHedge Research  ·  Published July 6, 2026  ·  ~11 min read  ·  Measurement study — not betting advice
Abstract

Between March and July 2026 we graded 9,811 Kalshi BTC 15-minute windows — every up/down signal our model fired, logged before the window settled and scored at settlement; price-capture-error rows are flagged and excluded, not deleted. Two things fall out of the data. First, when Bitcoin barely moves inside the window the outcome is a coin flip: in the near-flat bucket the market resolves the model's way 50.1% of the time — no better than chance — while windows with a large move resolve 98.9% of the time. Second, across the full sample the win rate simply tracks the price you pay: a contract entered near 100¢ resolves in your favor ~99.7% of the time, one entered at 80¢ or less about 53.4% — so the headline win rate is bought, not earned, and realized edge in expected-value (EV) terms is roughly zero before fees and slightly negative after.

The high published win rate is real, but it is mostly the market pricing near-certainty. Any informational signal that remains is small and fragile, and it disappears exactly when the window is flat. Near-flat windows should be read as coin flips.

Sample: 9,811 graded windows Period: March–July 2026 Market: Kalshi KXBTC15M Logging: pre-settlement; flagged, not removed
91.2%
Published BTC 15-min win rate (live), at a 91.7¢ average entry (96¢ median)
breakeven before fees at that price is 91.7% · Kalshi's fee pushes it higher (fee study)
12,160
Priced signals in the live feed
graded at settlement · rows whose entry price never captured are excluded, so this is smaller than the raw log
50.1%
Near-flat window win rate
a coin flip · this study's core finding
Live tiles update from our public feed every 30s. The analysis below is frozen on a fixed 9,811-window March–July 2026 sample; those study figures are stated as plain text throughout.
Finding 1

Flat windows are coin flips

When the move is tiny, settlement is decided by noise. The near-flat bucket wins 50.1% — chance.

Finding 2

The market is efficient

Win rate tracks the price paid. Pre-fee EV is ~zero everywhere; a high hit rate is not profit.

How Kalshi BTC 15-minute markets work

Before the findings, the mechanics — because the whole result follows from them.

Kalshi's KXBTC15M series lists a fresh contract every fifteen minutes. Each one asks a single binary question: at the close of this 15-minute window, will Bitcoin be up or down versus the window's opening price? You buy "Up" or "Down" for somewhere between 1¢ and 99¢. At settlement the contract pays $1.00 if it resolved your way and $0.00 if it did not. There is no partial credit and no in-between. Settlement is scored against the CF Benchmarks Bitcoin Real Time Index (BRTI), an index built from several exchanges' order books and averaged over the final 60 seconds, not against any single trade print, so the only thing that ultimately matters is which side of the opening average the closing average lands on. Our settlement study has the full rule.

Two structural facts shape everything downstream. The books are thin retail books — a handful of participants, modest depth, prices that can sit unchanged for seconds at a time. And a model watching the raw index can register a new state before the resting orders on Kalshi show any change. We used to describe the second fact as a lag that would close, and treat the distance between the index and the quoted price as where an informational edge lives. Our own order-book instrumentation went against that, and the correction is in our companion piece, The Kalshi Lag, retired →. What follows measures the record itself rather than the mechanism.

Keep the settlement rule in mind, because it is the hinge of Finding 1: the outcome is not "did Bitcoin go up a lot?" It is "was the index one cent above the open, or one cent below?" When the window's total move is only a few dollars on a roughly $64,000 contract, that question is essentially a fair coin.

Finding 1

The razor-flat coin flip

Sort every window by how far Bitcoin actually moved inside it, and the win rate is not flat — it climbs from a coin flip to near-certainty. The interesting part is the bottom of that ladder.

Win rate by size of the in-window move
Bar width = win rate. Red = coin flip; green = near-certain. Dashed line marks a true 50/50.
Move < 0.02% near-flat window
50.1%
▲ win rate climbs monotonically with the size of the move — intermediate move buckets fall between these two ends ▼
Move ≥ 0.20% decisive window
98.9%
The near-flat bucket sits right on the 50% line — statistically indistinguishable from a coin toss. As the realized move grows, the binary question ("which side of the open?") stops being close, and the win rate rises toward certainty. The headline number is dominated by the decisive windows, but a large share of live markets are near-flat, and those are where the model's apparent skill evaporates.

The flat-window rate is pinned to 50% every month

This is not a one-month artifact. Break the near-flat bucket out month by month across the whole sample and it never separates from a coin flip — the pattern is stable, not noise in a single slice.

Month (2026)Near-flat window win rateWindowsRead
March50.0%76Coin flip
April52.6%352Coin flip
May48.4%438Coin flip
June50.7%274Coin flip
July46.4%69Coin flip
Across all five months the near-flat bucket held at roughly 50.1% overall and never strayed meaningfully from a coin flip. Persistence like this is what tells you the result is mechanical, not a fluke.

The mechanic: the move is inside the noise

Why do flat windows behave like coins? Because there is almost nothing to measure. The median flat-window move ≈ $19.87 on a contract worth roughly $64,000 — about 0.03%. At that scale the outcome is not decided by any trend; it is decided by settlement mechanics and sampling noise: the exact tick the index happens to print at the close, which side of the open it lands on by a few dollars, ordinary micro-jitter. A $20 wobble on a $64k number is a rounding error, and a rounding error resolves like a coin.

This is also where the model is at its most misleading. In near-flat windows the model can still report a high model probability, and that number overstates reliability, because it is reading signal into a move that is statistically indistinguishable from noise. A 70% or 80% model probability on a window whose realized outcome is 50/50 is not an edge; it is the model being wrong half the time while reading high. Treat a high model probability in a flat window as a warning, not a green light.

Finding 2

The market is efficient — the win rate is priced in

Finding 1 shows where the apparent advantage disappears. Finding 2 shows why, even where the model is "right," being right is not the same as being ahead. Sort the same windows by the price you paid to enter, and the win rate tracks that price almost exactly.

Win rate by contract entry price
Bar width = win rate. The win rate you get is essentially the win rate you paid for.
Paid ≤ 80¢ priced as a toss-up
53.4%
▲ pay more → win more often, because you are buying the win rate ▼
Paid 100¢ priced as near-certain
99.7%
A contract the market prices near certainty (100¢) resolves in your favor about 99.7% of the time; one priced as a near toss-up (≤80¢) resolves your way about 53.4% of the time. In between, every bucket lands where its price says it should — the market has already done the pricing. This is what an efficient market looks like: the win rate is not a discovery, it is the ticket price.

Expected value by bucket: roughly zero, everywhere

Translate win rate and price into expected value per $1 staked and the picture is unambiguous. Because a payout of $1 at probability p costs about p dollars, a win rate that tracks the price leaves pre-fee EV at roughly zero across every bucket — and once Kalshi's fees come out, the residual tilts slightly negative.

Contract entry priceWin rate (hit rate)Pre-fee EV per $1After fees
80¢ or less (toss-up) 53.4% ≈ $0.00 slightly negative
100¢ (near-certain) 99.7% ≈ $0.00 slightly negative
Every price bucket in between lands in the same place: win rate ≈ price paid, pre-fee EV ≈ zero, post-fee EV slightly below zero. No bucket in the sample stood out as a place where the hit rate outran the price.

Put plainly: the win rate is bought, not earned. A high hit rate is not profit — you already paid for it in the entry price. We used to argue that a timing effect survived underneath that arithmetic. We no longer do: in expected-value terms across this sample the residual is roughly zero before fees and negative after, and our order-book snapshots on the sports products show no measurable price move after an alert. Read this record as a description of a market, not as a source of returns.

What this means for anyone looking at these markets

This is a measurement, not a recommendation. Here is how to read a headline win rate on 15-minute BTC without fooling yourself.

We publish the model's signals and grade them in the open because the honest version of this data is more useful than a marketing number. For the mechanism we argued, and the measurement that retired it, read The Kalshi Lag; for how the model is built and scored, see The Method. Everything here is for informational and entertainment purposes only. 18+ where legal — this is not betting advice.

More Bitcoin research: Kalshi BTC 15-minute fees and the win rate you need to break even · How Kalshi BTC 15-minute markets settle, and when a spot chart gets it wrong · Polymarket 5-minute vs Kalshi 15-minute Bitcoin markets

Related research: Do NFL contracts reprice slower than the scoreboard? → — the same hypothesis in a market where the price moves in jumps instead of drifting, and the order-book test it did not survive.

Common questions about this study

Are near-flat Kalshi BTC 15-minute windows a coin flip?

In our March to July 2026 sample, yes. Windows where Bitcoin moved less than 0.02% resolved the model's way 50.1% of the time, and the rate stayed near 50% in every month. The median flat-window move was about $20 on a price of roughly $64,000, which is inside settlement noise.

Does a high win rate on Kalshi BTC 15-minute contracts mean a profit?

No. In this sample the win rate tracked the price paid: contracts entered at 80 cents or less won about 53.4% of the time and contracts priced near certainty about 99.7%. Expected value was roughly zero before fees in every price bucket and slightly negative after Kalshi's fees.

How was this sample collected?

9,811 Kalshi KXBTC15M windows from March to July 2026, each logged before the window settled and graded at settlement. Rows whose entry price failed to capture are flagged and excluded, never deleted. The figures are frozen on that sample; the fees and breakeven study covers the record through October 8, 2026.

Methodology & get the data

The point of a study is that you can check it. Here is exactly what we did and where the raw data lives.

The sample

9,811 graded windows on Kalshi's KXBTC15M series, March–July 2026. Every up/down signal the model fired in that window is included.

The grading rule

Each signal is logged before the window's outcome is known, with the model probability and the live market price captured at signal time. The outcome is filled in automatically at settlement from Kalshi's official result, which settles on the CF Benchmarks BRTI. Wins and losses are scored the same way. No results are deleted and no losers are quietly dropped; a small number of early rows where the entry price failed to capture (logged as 0¢) are flagged and excluded from the count, not removed, and are still visible in the public log.

How to reproduce

Bucket the rows by realized in-window move (Finding 1) or by entry price (Finding 2), take the win rate per bucket, and compute EV as (win rate × $1) − price. The two charts above fall straight out.

The raw, per-signal log is public. Every graded window in this study — model probability, market price at signal, and settled outcome — is in the same feed:

Citations welcome. If you write about these markets, the CSV above is the primary source; this page is the canonical writeup. Dataset name for attribution: DegenHedge Kalshi Signal Dataset. Past performance does not guarantee future results.

Watch it grade in real time

You do not have to take our word for any of this — the honest version is the whole point.

The free, verifiable stuff comes first

Every signal this study is built on keeps going into a public results log and a downloadable CSV, graded win or loss at settlement with nothing pulled. That is the primary way to follow this work: free, and checkable against the CSV above. Our free Telegram proof channel carries MLB and NFL calls, and Bitcoin calls as graded recaps every 3 hours after each window closes; every one is also in the log.

⚠️

Risk reality — read before acting on anything here

These are 15-minute binary prediction-market contracts. Any single window can lose 100% of your stake. This study's own conclusion is that the win rate is priced in and realized expected value across the sample was roughly zero before fees and slightly negative after — a high hit rate is not a return. Nothing on this page is financial, investment, or betting advice.

Past performance does not guarantee future results. Trade only with money you can afford to lose. Must be 18+ or of legal age where you live. If gambling is a problem for you, call 1-800-GAMBLER.