Expected move explained: what the options market is telling you
How to read the expected move, why one standard deviation is the honest number, and how to use it to size trades and set targets.
Guides
The numbers behind an options trade, explained
Short, specific guides to the figures the calculator reports. Each one says what the number is, how it is computed, and what it does and does not tell you.
How to calculate the expected move from a straddle (with a worked example)
The straddle shortcut, why the 0.85 rule of thumb understates the range, and the sqrt(2/pi) correction that lines it up with implied volatility.
Max pain explained: how it is calculated and whether it actually pulls price
The exact max pain formula, what dealer hedging has to do with it, and what the evidence says about pinning into expiry.
0DTE expected move: sizing same-day SPX and SPY trades
Why the straddle method is the right one for zero days to expiry, how the range shrinks through the session, and where the usual mistakes are.
Earnings implied move vs actual move: how to tell if options are overpriced
Isolating the earnings-day move from the chain, comparing it with past prints, and deciding between buying and selling the event.
Put/call ratio: what it measures and what it does not
Volume vs open interest versions, why the "0.7 bullish, 1.2 bearish" rule fails on index products, and how to read it next to the expected move.
Implied volatility vs expected move: the square root of time rule
Turning an annualised IV number into a dollar range for any expiry, and why a 30% IV stock is not expected to move 30%.
Looking for the formulas themselves? They are all on the methodology page.