An Inside Day (ID) is contraction. An Outside Day (OD) is one form the subsequent expansion can take. Across 7 futures markets and 14 FX pairs, the expansion is real, but the Outside Day (OD) remains the minority outcome. Since January 1, 2020, an Outside Day (OD) has occurred in about 9–13% of sessions.
Outside Day, What's Next? Crabel Pattern Statistics across 7 futures markets and 14 FX pairs, from 2020 to date.
However, after an Inside Day (ID), that rises to 14–24%. After an IDnr4, the rate is usually a little higher, reaching about 30% on the Swedish Krona (USD/SEK). That is roughly twice the baseline rate. It is not a coin flip, and it is not a rule.
On the E-mini S&P 500 (ES), 42 of 184 Inside Days (ID) were followed by an Outside Day (OD): 22.8%, against a baseline of 12.5%. The other 142 were not. For the E-mini S&P 500, an IDnr4 did not improve the rate: it remained 22.8%. But it did raise the rate for the Dow (YM), from 22.3% to 27.5%; Gold (GC), from 18.2% to 27.1%; and most major FX pairs.
Futures show a cleaner pattern than FX. The E-mini S&P 500 (ES), Nasdaq-100 (NQ), Dow (YM), Crude Oil (CL), and Natural Gas (NG) sit around 21–24% after an Inside Day. The Euro (EUR/USD), Yen (USD/JPY), Forint (USD/HUF), and Rand (USD/ZAR) are closer to 14%. The pattern is the same, but the lift is smaller in FX pairs whose daily bars are defined by the New York session, even though the underlying market trades nearly around the clock.
What That Means
An Inside Day (ID) tells that the session stayed within the prior day's range. That is balance, not direction. The next session must make the decision. Crabel's framework is that contraction precedes expansion. The trade is the breakout in the next session, not a bet that the next bar will be an Outside Day (OD).
An Outside Day (OD) is the loud version of expansion: price takes out both extremes of the prior bar. But expansion can take quieter forms—a break of only one side, a trend day that never reaches the opposite extreme, or a move beyond the range that subsequently returns inside. Those moves can still deliver the expansion the setup was designed to capture. Waiting for an Outside Day (OD) means passing up most of the trades the pattern is meant to produce.
IDnr4 is the tighter version of the setup: the bar is inside the prior bar and has the narrowest range of the past four sessions. Crabel preferred it to an Inside Day (ID) alone, an NR4 alone, or an opening-range breakout (ORB) taken indiscriminately every day. The data broadly support that preference. In the table above, the Outside Day (OD) rate after an IDnr4 is usually a little higher than after a plain Inside Day (ID). But even here, an Outside Day (OD) remains the minority outcome.
What the Other Work Says
► Crabel trades the next session as a two-sided opening-range breakout (ORB) after an ID or IDnr4, unless the market is already running. In that case, he places the stop against the prevailing move and takes only the breakout in its direction. A wide-range day (WS) or an Outside Day (OD) means the expansion has already happened. It is not a fresh setup.
► Larry Williams treats the Inside Day (ID) as congestion and a potentially reliable short-term signal, but his published application is directional. In his course material, an Inside Day (ID) with a down close, when price was already below its level ten days earlier, was followed by a higher close the next day about 71% of the time in the S&P. That is a directional bias, not a breakout rule.
Williams' Outside Day Rule is a separate trade. An Outside Day (OD) that closes below the prior day's low is a buy; one that closes above the prior day's high is a sell. The logic is that the close signals rejection of the move beyond the prior extreme. Williams is fading the Outside Day (OD), not predicting that one will follow an Inside Day (ID) .
► Connors and Raschke took Crabel's IDnr4 setup and added explicit trade management. In Street Smarts, the rule is to place a buy stop one tick above the IDnr4 and a sell stop one tick below it for the next session only. If stopped out, reverse the position. If the trade is not profitable within two days, exit at the close.
Their central insight is useful: one can anticipate volatility expansion without knowing its direction. They also required a volatility filter—six-day historical volatility below half the 100-day reading—before taking the ID or NR4 setup (Street Smarts: The ID/NR4 Rules). The same idea appears in the popgun pattern, an Inside Day followed by an Outside Day, and in the NR7-Inside hybrid.
Later tests of a plain 30-minute opening-range breakout after an Inside Day have not consistently outperformed taking the breakout every day. Contraction narrows the opening range (ORB), but it does not, by itself, guarantee a better close-to-close result.
The patterns are valid from Monday, October 19, 5:30 p.m. ET through the session that ends Tuesday, October 20, at 5:00 p.m. ET.
What to Do After an ID or IDnr4
Do not enter on the bar that just printed. The pattern is yesterday's; the trade is in the next session. Prefer IDnr4 to a plain Inside Day (ID). The range is tighter, the contraction more pronounced, and in the Crabel Pattern Scanner sample the probability of a subsequent Outside Day (OD) is usually a little higher.
Use a two-sided breakout unless the intermediate trend is already running. If it is, take only the breakout in the trend's direction. A gap aligned with the run supports continuation; a break against it is the one to skip.
The entry is a break of the Inside Day's high or low, or a breakout from the opening range using Stretch—not a hope that the session will become an Outside Day (OD). If price breaks one side and holds, that is the trade. If it breaks both sides and closes back inside, the expansion has failed (Connors and Raschke's dual-stop version).
Expect an Outside Day (OD) roughly one session in four or five after an Inside Day (ID) in futures, and closer to one in six or seven in the quieter FX pairs. Size the trade for the more likely alternative. Most sessions will not engulf the prior range.
If the next session does produce an Outside Day (OD), the expansion has already occurred. Do not treat that bar as a fresh contraction setup. Williams would instead examine where it closed. A close below the prior low is his buy signal; a close above the prior high is his sell signal. That is a separate reversal trade, distinct from the breakout that followed the Inside Day (ID).
Stand aside when the Inside Day (ID) forms in choppy conditions with no established trend, or when the market opens beyond both sides of the range before you can execute the setup. The pattern is a contained session followed by a decision. If the market has already made that decision at the open, the setup is gone.
See also:
TPR (2026) - Crabel Pattern Scanner Stats.