BTC weekly surface: 1W ATM IV rises 1.70 volatility points

01 · Weekly summary

What changed across the BTC volatility surface.

Across the six headline tenors, ATM IV averaged +0.61 volatility points, RR25 +0.62 volatility points and BF25 +0.16 volatility points between the stored endpoints.

Weekly universe roll: added 14AUG26, 25JUL26, 26JUL26, 27JUL26, 28JUL26; removed 18JUL26, 19JUL26, 20JUL26, 21JUL26, 24JUL26. Listed-expiry changes use contracts present at both endpoints.

02 · ATM volatility

Week-end against week-opening ATM volatility.

03 · During the week

Ranges and largest day-to-day repricings.

The generator sampled the final successful BTC surface on each of 8 observed UTC dates, so endpoint changes can be read alongside the path taken during the week.

04 · Skew and convexity

RR25 and BF25 over the seven-day window.

RR25 moved towards calls, averaging +0.62 volatility points across the six headline tenors. The largest eligible RR25 movement was at 3M. Negative RR25 denotes a richer put wing.

BF25 increased, averaging +0.16 volatility points across the six headline tenors. The largest eligible BF25 movement was at 1M.

05 · Listed expiries

Common exchange maturities at both weekly endpoints.

06 · Smile movement

Reconstructed SVI smiles for common expiries.

Each overlay compares the fitted smile at the two weekly endpoints. Ultra-short expiries remain visible but do not determine headline rankings.

Weekly surface movement heatmap

Each cell is the fitted IV change in volatility points from week start to week end.

07 · SVI diagnostics

Weekly movement in a, b, rho, m and sigma.

Parameter changes are shown directly from the stored endpoint fits; no causal interpretation is attached.

08 · Methodology and provenance

Generated from Derivasys surface data only.

Week-end snapshot

24 Jul 2026, 23:59 UTC

Week-opening snapshot

17 Jul 2026, 23:59 UTC

Comparison

Nearest successful surface snapshots approximately seven days apart

Source

Derivasys proprietary historical SVI surface database

Snapshot selection

The final successful BTC surface on each observed UTC date is included. This report contains 8 daily snapshots; an approximately seven-day window contains eight observations when both the start and end dates are present.

Calculations and commentary

Metrics and takeaways are deterministic. Daily headlines and introductions may be model-assisted, constrained to the same stored facts; weekly prose is deterministic.

RR convention

25-delta call IV minus 25-delta put IV

BF convention

Average 25-delta wing IV minus ATM forward IV

Fixed tenors

Fixed-tenor measures are interpolated independently at 1W, 2W, 1M, 3M, 6M, 9M and 1Y; headline rankings prioritise 1W, 2W, 1M, 3M, 6M and 1Y.

Smile reconstruction

Listed-expiry smiles are reconstructed from stored SVI total-variance parameters on a fixed log-moneyness grid.

Ultra-short expiries

Expiries with fewer than 2 full days remaining stay in detailed tables but are excluded from headline rankings. Settlement proximity, time decay, changing liquidity and fewer quotes can exaggerate their changes.

Causal claims

The report describes observed surface changes only and does not infer unsupported market drivers, spot moves, flows or forecasts.

This report contains 8 daily snapshots because both the start and end dates are observed within the approximately seven-day window.