Session Replay: How to Review Intraday GEX Changes
- Session Replay lets you scrub back through the trading day to see GEX at any past point in the session.
- Use it to understand why a key level held or broke — not just that it did.
- Perfect for post-market review: what was the GEX structure at the exact moment of a breakout?
- Data is stored every 30 seconds throughout the session.
What is Session Replay?
GEXBoard saves a snapshot of the full GEX structure every 30 seconds during market hours. Session Replay lets you scrub through those snapshots using a timeline slider, watching how the Call Wall, Put Wall, Zero Gamma level, and dealer regime evolved throughout the day.
Think of it as a DVR for dealer positioning. Instead of only knowing what the GEX structure looks like right now, you can rewind to 10:15 AM and see exactly what it looked like in the minutes before that flush — or before that squeeze. The context that was available to a structural trader at that moment, reconstructed precisely.
This separates GEXBoard from single-snapshot tools. Positioning isn't static — it shifts as large players adjust their books, as expirations roll, and as the underlying moves. Session Replay captures every one of those shifts.
How to Use Session Replay
Step 1 — Open the Replay Panel
Click the "Replay" button in the dashboard toolbar (clock icon). The timeline slider appears at the bottom of the screen. The current live view pauses and you enter replay mode — the Dealer Mode badge, GEX chart, and all key level indicators will now reflect the selected historical moment rather than the live feed.
Step 2 — Scrub the Timeline
Drag the slider left to go back in time. The GEX chart, key levels, and Dealer Mode badge all update to reflect that moment in the session. The time indicator above the slider shows the exact time of the snapshot you're viewing. Scrubbing is smooth — every 30-second snapshot is available from market open at 9:30 AM ET through the current time (or session close if you're reviewing after hours).
Step 3 — Use the Playback Controls
Hit Play to watch the day unfold automatically. Adjust playback speed (1x, 2x, 4x). Pause at any moment to analyze the structure in detail. The 4x speed is particularly useful for scanning the full session quickly to identify the key structural events of the day before drilling in on the specific moments that matter.
Step 4 — Note Key Transitions
Watch for moments when the Call Wall or Put Wall shifted, or when the regime badge flipped. These are the high-information moments in the session. When a wall moves significantly, it means large options positioning has changed at that strike — dealers have repriced their exposure. These moments often precede or coincide with price moves in the underlying.
When to Use Session Replay
| Use Case | Situation | How to Use Replay |
|---|---|---|
| Post-trade review | You took a loss on a breakout trade | Scrub back to entry time — was the GEX structure actually supporting the trade? |
| Morning prep | Previous session had unusual action | Review yesterday's session to understand what structural changes occurred |
| Pattern building | You want to study how walls behave at specific times | Build a mental model of how GEX evolves from open to close |
What to Look For
Wall migration: Did the Call Wall move higher (bullish repositioning) or lower (dealer hedging increasing)? The Gamma Migration panel shows ↑↓ arrows for each wall. In replay, you can watch the migration in motion — seeing which walls are sticky and which shift frequently is a core skill for structural traders.
Regime transitions: At what time exactly did Dealer Mode flip? Was it at the open, midday, or into the close? Flips at the open carry different meaning than flips into the close. A Short Gamma flip in the final 30 minutes of trading can have significant overnight implications as dealers carry that position into the next session.
0DTE influence: On expiration days, toggle to the 0DTE DTE filter in replay — watch how the 0DTE structure collapses throughout the day as contracts expire. The gravitational pull of 0DTE gamma can be seen dramatically in the replay as large 0DTE positions unwind into expiration, often causing the GEX profile to thin out at near strikes as the session progresses.
GEX spikes: Large sudden changes in GEX at a specific strike often signal institutional options activity at that level. In replay, these appear as abrupt jumps in the bar height at a specific strike. When you see a spike, note the time — then cross-reference with the price action to understand the trade context.
Analyze today's GEX structure with Session Replay
Full intraday replay, 30-second snapshots, and live regime tracking. Pro plan includes Session Replay with every session.
Frequently Asked Questions
How far back does replay data go?
Within the current trading session only. Snapshots are taken every 30 seconds from market open. Historical multi-day data is available in the GEX History tab (5-day view), but the frame-by-frame replay is session-scoped. If you want to review a prior session's structure, the GEX History tab shows daily summary data for the past 5 trading days.
Can I use replay for pre-market hours?
No, GEX data requires active options trading to be meaningful. Replay covers regular trading hours (9:30 AM – 4:00 PM ET) when options volume is active. Pre-market options volume is typically too thin to produce a reliable GEX structure, so pre-market snapshots are not captured or replayed.
Is replay available on all plans?
Session Replay is available on Pro and Trader plans. Starter plan includes the current live view only. If you're on Starter and want to access replay, you can upgrade to Pro at any time from your account page — your existing session data will be accessible immediately after upgrading.