Compare Volatility Skew

Compare IV across one expiration's strikes

Volatility Skew shows implied volatility by strike or delta, with up to eight selected expirations for comparison. Open it on Map → Volatility Analysis or alongside IV surface. Strike space emphasizes prices, while delta space compares positions on the modeled sensitivity scale. These are related views of eligible option inputs, not independent measurements of future realized volatility.

Build an expiry comparison

Start with one expiration and add others only after checking its source points.

1. Choose the underlying, session, date and valuation minute.
2. Select one available expiration.
3. Choose strike or delta space.
4. Hover points to inspect IV and identity.
5. Add up to the supported eight expirations.
6. Read the available skew statistics and preserve their convention when comparing dates.

Interpret shape and summary statistics

A slope can reflect different IV at different strikes or delta bands. Risk reversals and butterflies summarize selected parts of that shape using their documented convention; they are not quoted multi-leg orders. Delta-space positions depend on model values as well as prices. A curve can contain holes when eligible solves are missing, and a line joining usable points should not imply an executable market exists at every intermediate coordinate.

Worked example: strike and delta views differ

Compare the same two expirations in strike space, then delta space. A shared strike can be near the money for one context and have a different modeled delta in another. The apparent alignment can shift even though each contract's IV is unchanged. Inspect point identities rather than assuming equal horizontal positions mean equal strikes in both modes. Keep the valuation minute fixed so you do not mix coordinate changes with changing market inputs.

Troubleshoot missing points or unstable comparisons

Check the expiry selection and required historical input before widening every control. A stale quote or invalid IV solve should remain unavailable. Compare the same side/convention and minute across tools. If a surface-node action opens skew for an expiry, confirm that expiry before expecting the full previous multi-expiry comparison. A useful ticket names axis mode, expiration list, exact point and its input time instead of saying the curve looks wrong.

Compare volatility on consistent assumptions

Implied volatility is inferred from eligible option inputs under a model; realized volatility summarizes an observed underlying-price sample. Neither is an executed underlying price or a guarantee about a future move. Expiration, strike or delta band, valuation time, calendar/trading-time convention and available quote coverage all matter. A blank or invalid IV solve should stay unavailable rather than being treated as zero volatility or replaced by an unrelated contract's value.

For comparisons, first align the underlying, trading date and session. Then match the relevant expiration or maturity convention and inspect dated source inputs. A quote snapshot delivered now can still contain older observations. A historical slider selection needs eligible historical inputs; the current chain cannot manufacture an earlier smile. Closed or partial sessions can have fewer usable points. When a curve looks unusual, inspect a specific node and neighboring inputs instead of inferring a broad market regime solely from a smooth line or a color change.

Use smile statistics without assuming executable spreads

A risk reversal or butterfly is a derived summary of selected IV points under a convention. It does not provide all leg quotes, transaction costs or an executable order. A skew difference between expirations can reflect maturity-specific inputs; it should not automatically be attributed to a particular event without independent evidence. Inspect the actual strikes/deltas and quote quality used for the comparison, especially when a far-wing point has sparse usable input.

For a repeatable check, select one expiry, record several observed nodes, then add a second expiry and compare in the same coordinate mode. Changing to delta space is a separate experiment, since horizontal alignment depends on model delta. If the curve contains holes, do not estimate an unobserved point by eye and report it as quoted IV. Surface interpolation labels and skew source nodes can have different presentation roles, so inspect provenance before expecting a visually smooth surface to equal every native skew point. Preserve exact expiry, axis mode and valuation time when sharing the result.