0DTE options research: same-day gamma and same-day risk

What same-day expiry research is actually asking

The question in 0DTE research is not which direction the market will go. It is where same-day contract exposure has concentrated relative to the current price, and whether price is interacting with those areas as the session runs down. That is a description of positioning, and it stops well short of a forecast.

0DTE activity concentrates in index and large ETF products, where daily expirations exist and liquidity supports them. Cboe has published extensively on how that share of volume has grown and what it does and does not imply about market structure. Single names with weekly expirations behave differently and generally do not support the same routine.

• Where is same-day gamma concentrated relative to spot right now?
• Is that concentration above the price, below it, or straddling it?
• As the session progresses, does price approach those areas, stall near them or ignore them?
• What would falsify the reading — and is it being written down before or after price moves?

Gamma concentration around spot

Gamma exposure estimates how sensitive hedging requirements are to a change in the underlying price at each strike. The 0DTE GEX view shows that estimate for same-day contracts around the current price, which is where same-day gamma is largest and where it changes fastest.

The reason it concentrates is arithmetic rather than sentiment. An option expiring in hours has almost no time value away from the money, so its delta changes very sharply as price crosses the strike. That sharpness is what gamma measures, and it is why a same-day chart looks like a spike near spot rather than a broad curve across the chain.

• Identify the largest same-day concentrations above and below the current price.
• Note whether the concentration is call-heavy, put-heavy or balanced around spot.
• Check how far each concentration sits from spot in points, not in visual distance on a chart.
• Re-check after any material move: same-day gamma redistributes quickly when price crosses a strike.

Magnet Levels: model output, not a level that must hold

Magnet Levels ranks strikes by a flow-signed estimate of dealer gamma and labels call walls, put walls, modeled magnets and the gamma-flip area. Every one of those labels describes a model, computed from public data, about positions that are never publicly disclosed.

The correct use is comparative and provisional: this strike carries more estimated sensitivity than that one, so it is worth watching whether price behaves differently there. The incorrect use is treating a wall as support or a magnet as a target. Price ignoring a modeled level is not a malfunction; it is evidence that the model's assumptions did not hold today, and it deserves to be recorded as such.

• Read the confidence gate and sample notes before using any relative ranking.
• Treat wall, magnet and flip as model vocabulary, not as market guarantees.
• Watch price, execution pressure and volume as spot approaches a level rather than assuming reaction.
• Record when price passes straight through a level: invalidation is the most useful observation available.

Why same-day gamma decays through the session

Same-day exposure is not stable across the session. As the close approaches, contracts far from spot lose essentially all of their sensitivity, while contracts near spot become extraordinarily sensitive to small price changes. The overall gamma profile therefore narrows and intensifies rather than simply shrinking.

The practical consequence is that a 0DTE read taken at the open describes a different exposure landscape from one taken in the final hour, even if price has not moved much. A routine that reads the chart once in the morning and refers back to it at three o'clock is describing something that no longer exists.

Risk: how fast a same-day option reaches zero

This section is deliberately blunt. A 0DTE option has hours to live. If the underlying does not reach the strike by the close, a long position expires worthless and the entire premium is lost. This is not an unusual outcome that careful analysis avoids; it is the ordinary outcome for out-of-the-money contracts, and no dashboard changes it.

The short side carries a different and larger problem. Selling same-day options can produce losses far exceeding the premium received, uncovered call writing carries theoretically unlimited risk, and assignment can occur on in-the-money contracts. Options involve significant risk and are not suitable for all investors. Read the OCC Characteristics and Risks of Standardized Options document before trading any of this, and note that Realtime Options provides research software rather than advice.

• A long 0DTE option that finishes out of the money expires worthless: the loss is the full premium.
• Time value drains fastest on the final day, so a directionally correct view can still lose if it arrives late.
• Gaps and fast moves can change a same-day position's value within minutes, in either direction.
• Short same-day options can lose substantially more than the premium received; uncovered calls are theoretically unlimited.
• Assignment risk applies to in-the-money short contracts, including on expiry day.
• Realtime Options issues no signals, entries, exits or position sizes, and is not a broker-dealer or investment adviser.

Why the trial cannot test this routine properly

The 7-day trial runs on 15-minute delayed data. For a contract with hours of life and an exposure profile that reshapes through the session, a 15-minute delay is not a minor handicap — it describes a state that has already changed. This is stated plainly because the alternative is letting a trial user conclude the routine does not work when the timing was never available to them.

Near-real-time analytics are on the $25 per month Pro plan. Near-real-time still means licensed third-party market data, not a direct exchange feed, and it is still research infrastructure rather than execution infrastructure.

• Trial, 15-minute delayed: usable for learning the screens and reviewing a completed session afterwards.
• Pro, near-real-time: usable for watching same-day exposure change as the session runs.
• Neither: order entry, routing, or any claim of speed advantage over professional participants.

What 0DTE research cannot tell you

Gamma exposure is a model built on public data. It does not know any dealer's actual inventory, the hedges held against it, or the offsetting exposure sitting in a different product entirely. Two reasonable models using the same public data can produce different level rankings.

Same-day flow inherits every limitation of ordinary flow and adds speed. Side remains an estimate, opening and closing remain indistinguishable in volume, and open interest — which would settle the question — is published once daily after the close, which is after every same-day contract has already expired.

• It cannot confirm dealer positioning, only estimate it from publicly available data.
• It cannot guarantee that price will react at, stop at or be drawn to any modeled level.
• It cannot distinguish same-day opening activity from closing activity in real time.
• It cannot use open-interest confirmation, because same-day contracts expire before the update publishes.
• It cannot make a same-day position less risky; the routine describes exposure, it does not manage it.

Questions people ask about this