Zero-DTE Magnet

Q: What is a zero-DTE magnet?

A zero-DTE magnet is the 0DTE strike with the highest absolute gamma exposure. On expiration days, dealer hedging at this strike creates a gravitational pull on price. When dealers are long gamma at the magnet strike, they buy dips and sell rips around it, causing price to oscillate near the strike. This effect intensifies as the close approaches because 0DTE gamma accelerates into expiry.

Q: How does the 0DTE magnet differ from gamma flip?

The gamma flip is the price level where net GEX crosses zero (the boundary between positive and negative gamma regimes). The 0DTE magnet is the specific strike with the highest gamma concentration on expiration day. They can coincide but often differ. The gamma flip determines the regime; the 0DTE magnet identifies the most likely pinning target within that regime.

Q: How reliable is the 0DTE magnet as a price target?

The 0DTE magnet is most reliable during low-volatility, positive-gamma environments where dealer hedging flows dominate directional trading. In negative gamma environments or during high-impact news events, the magnet effect weakens because directional momentum can overpower dealer hedging. The magnet also becomes more powerful as the close approaches, since 0DTE gamma accelerates into expiry.

Q: How do I get the 0DTE magnet via API?

FlashAlpha's GET /v1/exposure/levels/{symbol} endpoint returns the zero_dte_magnet field in the levels object. This endpoint is available on the Free tier. Example: curl -H 'X-Api-Key: YOUR_KEY' https://lab.flashalpha.com/v1/exposure/levels/SPY

Q: Why does Zero-DTE Magnet matter for trading?

The 0DTE magnet is the strike that pulls price in on expiration day. With same-day options now dominating SPX volume on expiry days, 0DTE gamma concentration can override the full-chain picture — especially in the final 1–2 hours. Retail 0DTE scalpers, index traders, and pin specialists all use it as the primary intraday target.

Q: When is Zero-DTE Magnet good versus bad for a trader?

The magnet is good for 0DTE pin plays on expiry day in positive-gamma regimes. It's useless on non-expiry days (no 0DTE chain to generate a signal), and dangerous in negative-gamma regimes where price breaks through rather than pinning. Don't anchor any non-expiry trade to a 0DTE magnet.

Canonical definition, mechanics, interpretation rules, and API reference for the 0DTE gamma magnet strike.

Definition

The 0DTE strike with the highest absolute gamma exposure. On expiration days, dealer hedging flows concentrate at this strike, creating a gravitational pull that attracts price action — especially in the final hours of trading when 0DTE gamma accelerates.

Identification

zero_dte_magnet = argmax( |GEX(strike)| ) for 0DTE expiry only

The strike with the largest absolute per-strike GEX among contracts expiring today. Computed from 0DTE gamma and open interest only — non-0DTE expirations are excluded.

Inputs

0DTE per-strike GEX open interest spot price

Output

zero_dte_magnet (strike price)

Interpretation

Positive gamma at magnet: Strong pinning effect. Dealers buy dips and sell rips around the strike, pulling price back toward it.
Negative gamma at magnet: Repulsion effect. Price accelerates away from the strike once breached as dealer hedging amplifies the move.
Magnet near spot: Maximum effect. The closer spot is to the magnet, the stronger the hedging flow influence on price action.

How the 0DTE Magnet Works

On any expiration day, the 0DTE options chain has a unique property: gamma is enormous near the money and falls off sharply away from it. The strike where this gamma is maximized becomes a focal point for dealer hedging. If dealers are net short options at that strike (the common case), they must continuously re-hedge as price moves toward or away from it.

In a positive-gamma environment, this hedging creates a pinning effect. Each time price rises above the magnet, dealers sell to re-hedge; each time it falls below, they buy. The result is price oscillating around the magnet strike, especially when no strong directional catalyst is present. This is why 0DTE expiration days often show tight ranges in the final hours.

The magnet effect strengthens throughout the day as gamma acceleration increases. By the final hour, 0DTE gamma can be 8-10x larger than 7DTE gamma, making the magnet the single most important intraday level. Traders who identify the magnet early can position for mean-reversion around it or use it as a stop-loss reference.

Get 0DTE Magnet via API

Endpoint

GET /v1/exposure/levels/{symbol}

Tier

Free

Parameters

symbol (path, required) — underlying ticker, e.g. SPY

Response field

{
  "symbol": "SPY",
  "levels": {
    "zero_dte_magnet": number,
    "gamma_flip": number,
    "call_wall": number,
    "put_wall": number,
    "highest_oi_strike": number
  }
}

curl -H "X-Api-Key: YOUR_KEY" \
  https://lab.flashalpha.com/v1/exposure/levels/SPY

import requests
r = requests.get(
    "https://lab.flashalpha.com/v1/exposure/levels/SPY",
    headers={"X-Api-Key": "YOUR_KEY"}
)
d = r.json()
print(f"0DTE Magnet: {d['levels']['zero_dte_magnet']}")

const r = await fetch(
  "https://lab.flashalpha.com/v1/exposure/levels/SPY",
  { headers: { "X-Api-Key": "YOUR_KEY" } }
);
const d = await r.json();
console.log(`0DTE Magnet: ${d.levels.zero_dte_magnet}`);

Magnet vs Other Key Levels

The 0DTE magnet is one of several gamma-derived levels, each with distinct mechanics. The gamma flip marks the regime boundary (positive vs negative gamma). The call wall and put wall mark the strikes with the most concentrated call/put gamma across all expirations. The magnet is unique because it is 0DTE-only and represents the most intense intraday hedging concentration.

When the magnet aligns with the gamma flip or highest OI strike, the pinning effect is maximized. When they diverge, the magnet still exerts pull on an intraday basis while the full-chain levels influence multi-day positioning.

Why Zero-DTE Magnet Matters for Trading

TL;DR

The 0DTE magnet is the strike with the highest same-day gamma — price pulls toward it into the close on expiry days, nothing else.

What it measures: The strike with the largest gamma exposure among options expiring today.
What it signals: The intraday gravitational target for same-day options flow. Relevant only on expiry day, only in the last few hours.
Why we measure it: 0DTE flow has ballooned to ~50% of SPX volume on expiry days. The magnet is the single level 0DTE gamma concentrates at.
Who uses it: 0DTE scalpers, day traders, closing-auction specialists, index ETF pin traders.

How to read Zero-DTE Magnet

Spot below magnet on expiry day

Positive drift toward magnet
Call-dominant 0DTE flow
Dealers buy into close
Pin-to-magnet setup

Good for: long toward magnet, short OTM calls above

Spot above magnet on expiry day

Negative drift toward magnet
Put-dominant 0DTE flow
Dealers sell into close
Short-to-magnet setup

Good for: short toward magnet, short OTM puts below

Non-expiry day / diffuse 0DTE OI

No 0DTE magnet effect
Full-chain GEX dominates
Ignore the magnet label
Typical Tue/Wed reading

Off

Rules of thumb

Only trade on expiry day. Non-expiry sessions don't have a meaningful 0DTE chain — magnet is noise.
Effect strengthens after 2pm ET. 0DTE gamma peaks into the close. Early session the magnet is weaker.
Fade only in positive gamma. In negative gamma, price blows through the magnet rather than pinning.
Watch magnet shifts intraday. New 0DTE volume reshapes the magnet. Refresh frequently.
Pair with pin risk. Magnet identifies the strike. Pin risk scores the probability.

Related Concepts

Pin Risk

The risk that price settles exactly at a strike at expiration — the 0DTE magnet is the most likely pinning candidate.

Gamma Flip

The price level where net GEX crosses zero — determines whether the magnet attracts (positive) or repels (negative).

Gamma Exposure (GEX)

Net dealer gamma across the full option chain — the magnet is the 0DTE-specific peak of this distribution.

Highest OI Strike

The strike with the most open interest across all expirations — often aligns with the 0DTE magnet on expiry days.

Learn More

API documentation

/v1/exposure/levels/{symbol}

Full endpoint reference for key levels including 0DTE magnet, gamma flip, call wall, and put wall.

Interactive tool

Live GEX Chart

Visualise per-strike gamma exposure with 0DTE overlay for any US equity or ETF.

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