An at-the-money straddle is a call and a put bought at the same, near-spot strike. Its combined price is one of the most useful numbers on the board: it's the market's own estimate of how far SPY is likely to move over the option's life, in dollars.
Why the straddle equals the move
A straddle profits from movement in either direction and loses if price sits still, so its price is the market pricing movement. If the at-the-money straddle for today costs about $5.00, the options market is effectively saying SPY's expected move for the session is roughly ±$5. It's implied volatility translated from an abstract percentage into a concrete dollar range you can read straight off the chain.
Reading it in practice
A common shortcut: the at-the-money straddle price approximates the one-standard-deviation expected move, and traders often shave it slightly (multiply by ~0.85) for a tighter estimate of the likely range. Either way, the straddle gives you today's realistic playing field without any math — add and subtract it from spot to get the expected high and low.
The straddle price isn't a trade idea — it's the market handing you the day's range in dollars. Read it, don't fight it.
Using it as a scalper
The expected move frames every other level. A target beyond the straddle-implied range is a low-probability reach; a fade back toward the middle from the edge of the range is the calmer, higher-odds play in a stable regime. It's a reality check on ambition — and it's exactly how NoVo derives the expected-move band it draws on the dealer map, so you're always sizing your target to what the day can actually deliver.