RR25 moved towards calls, averaging +0.92 volatility points to -0.71 volatility points across the six available headline tenors. Negative RR25 denotes a richer 25-delta put wing under the call-minus-put convention.
BF25 decreased, averaging -0.23 volatility points to 2.19 volatility points across the six available headline tenors. BF25 measures the average 25-delta wing premium over ATM IV.
Contracts with fewer than 2 full days to expiry remain in the tables but are excluded from headline rankings. Settlement proximity, time decay, changing liquidity and fewer quotes can exaggerate their changes.
0.6d
ATM IV change
21AUG26, +8.16 vol pts1.6d
ATM IV change
22AUG26, +4.40 vol pts
10 · Volatility term structure
Today against the previous 24-hour snapshot.
Only fixed tenors bracketed by listed expiries at both snapshots are charted. The listed-expiry table preserves the observable exchange maturities underneath those interpolated points.
CurrentComparison snapshot
Expiry
Time left
Forward now (USD)
Forward change (USD)
ATM IV now
ATM IV change
RR25 change
BF25 change
21AUG26Expiry effect
0.6 days
72,301.62
+3523.55 USD
46.84%
+8.16 vol pts
+0.13 vol pts
-1.21 vol pts
22AUG26Expiry effect
1.6 days
72,317.1
+3531.53 USD
43.39%
+4.40 vol pts
-0.64 vol pts
-0.02 vol pts
23AUG26
2.6 days
72,326.53
+3533.47 USD
37.36%
+2.03 vol pts
+0.22 vol pts
+0.16 vol pts
28AUG26
7.6 days
72,373.67
+3543.14 USD
38.70%
+2.75 vol pts
+0.30 vol pts
-0.10 vol pts
4SEP26
14.6 days
72,436.36
+3551.69 USD
36.77%
+1.97 vol pts
+1.47 vol pts
-0.31 vol pts
25SEP26
35.6 days
72,629.6
+3582.81 USD
37.71%
+0.30 vol pts
+0.70 vol pts
-0.20 vol pts
30OCT26
70.6 days
72,946.4
+3615.65 USD
38.41%
-0.11 vol pts
+1.21 vol pts
-0.31 vol pts
25DEC26
126.6 days
73,463.19
+3686.78 USD
40.66%
-0.14 vol pts
+1.44 vol pts
-0.18 vol pts
26MAR27
217.6 days
74,216.51
+3707.24 USD
41.25%
-0.19 vol pts
+1.03 vol pts
-0.19 vol pts
25JUN27
308.6 days
74,973.76
+3727.82 USD
42.29%
-0.26 vol pts
+0.88 vol pts
-0.28 vol pts
11 · Smile movement
Reconstructed SVI smiles for every common expiry.
Each overlay uses the stored five-parameter SVI fit and the snapshot-specific time to expiry. Ultra-short expiries are displayed but do not determine the headline ranking.
21AUG26rotation towards calls · wing steepening22AUG26rotation towards puts · wing steepening23AUG26rotation towards calls · wing steepening28AUG26parallel shift higher · rotation towards calls · wing flattening4SEP26rotation towards calls · wing flattening25SEP26rotation towards calls30OCT26rotation towards calls25DEC26rotation towards calls26MAR27rotation towards calls25JUN27rotation towards calls
Surface movement heatmap
Each cell is the fitted IV change in volatility points. Rows are listed expiries; columns run from the put wing through ATM to the call wing.
IV lowerIV higher
21AUG26
22AUG26
23AUG26
28AUG26
4SEP26
25SEP26
30OCT26
25DEC26
26MAR27
25JUN27
-0.30kATM+0.30k
Evidence, source data and methodology
Report comparison baseline → current snapshot
2026-08-19 16:36:00 UTC → 2026-08-20 16:36:00 UTC
Changes use these stored market-snapshot baselines. The comparison baseline may differ from the snapshot used in the previous published edition.
Original report summary
Front-end ATM IV rose while long-dated IV eased; RR25 shifted toward calls and BF25 declined.
At report cutoff · Levels and stored endpoint changes
What matters now
Vol: BTC 1W ATM IV 38.54% · Δ +2.70 vol pts
Skew: BTC 1W RR25 1.64 vol pts · Δ +0.14 vol pts
Wings: BTC 1W BF25 2.14 vol pts · Δ -0.12 vol pts
Vol
BTC 1W ATM IV 38.54% · Δ +2.70 vol ptspercentile rank 86.7% by absolute move · 30-day window (n=30)
Skew
BTC 1W RR25 1.64 vol pts · Δ +0.14 vol ptspercentile rank 8.5% by absolute move · full history (n=118)
These diagnostics preserve the fitted-surface audit trail without competing with the main market story.
Show SVI parameter changes and normalized Greeks
SVI diagnostics
Daily movement in a, b, rho, m and sigma.
Among ranking-eligible expiries, the largest absolute rho change occurred at 26MAR27; the largest sigma change occurred at 4SEP26.
Expiry
Δ a
Δ b
Δ rho
Δ m
Δ sigma
Smile classification
21AUG26
-0.04930
+0.01090
+0.00640
+0.04600
+0.42450
rotation towards calls, wing steepening
22AUG26
+0.00370
-0.01060
-0.01970
-0.00530
+0.01020
rotation towards puts, wing steepening
23AUG26
+0.00940
-0.00850
+0.02580
+0.01020
-0.04050
rotation towards calls, wing steepening
28AUG26
-0.02910
+0.01640
+0.01310
+0.01460
+0.13390
parallel shift higher, rotation towards calls, wing flattening
4SEP26
-0.06090
+0.01690
+0.07870
+0.00930
+0.23860
rotation towards calls, wing flattening
25SEP26
-0.04320
+0.01680
+0.07800
+0.02940
+0.14780
rotation towards calls
30OCT26
-0.04790
+0.01250
+0.09940
+0.03000
+0.16390
rotation towards calls
25DEC26
-0.04820
+0.00560
+0.10290
+0.02010
+0.13530
rotation towards calls
26MAR27
+0.04080
-0.07240
+0.18950
+0.21160
+0.00670
rotation towards calls
25JUN27
-0.00320
-0.06530
+0.13280
+0.13280
+0.12010
rotation towards calls
Current surface characteristics
Where normalized model Greek intensity is highest.
These are comparable Black-forward Greeks for a one-BTC ATM-forward call at each listed expiry—not portfolio exposure, open interest or a prediction of dealer positioning.
Thresholds are asset-specific policies recorded in this edition. Each window is assessed independently; returns spanning gaps are excluded. Partial estimates may miss volatility during gaps.
RV coverage and methodology
BTC · Unavailable · Surface cutoff 20 Aug 2026, 16:36:00 UTC · 7D coverage not recorded / not recorded required · largest 7D gap not recorded / not recorded maximum · maximum gap not recorded. RV suppressed — valid 7D coverage was not recorded. Full 7D coverage policy was not recorded.
Derivasys proprietary historical SVI surface database
Comparison window
Nearest successful surface snapshots approximately 24 hours apart
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.
Greek normalization
Black forward Greeks for a normalized one-BTC ATM-forward call, zero rate, fitted SVI IV
Catalyst policy
Only sufficiently relevant, reliably sourced events are shown; otherwise no catalyst is assigned.
