SPX dealer gamma — Tuesday, January 21, 2025

dealer positioning for the session, reconstructed from the 0DTE options tape

These are the CLOSING levels for 2025-01-21. Where the SPX dealer book stands right now — the current zero-gamma flip, call resistance and put support — is on /now, free, at least fifteen minutes behind the tape.

SPX opened at 6,027.62 and closed at 6,048.81, up 0.35% on the session (range 6,008.22–6,050.45). The close sat 83.6 points above the zero-gamma flip at 5,965.2 — dealer hedging in vol-dampening territory. Call resistance 6,050, put support 6,070. 0DTE ATM IV opened at 9.4%.

Price stayed on one side of the flip for the whole session. The tape spent 84% of the day above VWAP. The expected-hold band 5,965.2–6,069.0 contained the entire session.

Open → Close6,027.62 → 6,048.81 (+0.35%)
Session range6,008.22 – 6,050.45
VWAP at the close6,036.01
Zero-gamma flip5,965.2
Call resistance6,050
Put support6,070
Expected-hold band5,965.2 – 6,069.0
0DTE ATM IV at the open9.4%
Regime at the closepositive gamma
Close vs flip+83.6
Net-gamma percentile100
Open this session in the terminal →

The terminal replays the full session minute by minute: dealer gamma, vanna and charm by strike, the flip and hold levels as they moved, IV and realised vol side by side. Every historical session is free and needs no account. New to these terms? Start with what GEX is. Measured across the whole archive: how often these levels hold and how far SPX travels before the close.

Measurements are model output derived from public trade and quote data; they are approximations and can be wrong. Nothing here is investment advice — see the Terms.