6 of 6 headline tenors were comparable at both endpoints. The largest ATM IV move was 1M at +0.41 volatility points, to 33.39%.
Derived directly from structured Derivasys surface data
03 · Catalyst check
31 Jul 2026, 13:34 UTC to 01 Aug 2026, 13:34 UTC
No relevant catalyst identified.
No qualifying context was identified after a healthy coverage check.
04 · Detailed analysis
What changed across the BTC volatility surface.
Front end
Front-end ATM IV increased, averaging +0.12 volatility points to 32.37% across 1W, 2W and 1M.
Long end
Long-dated ATM IV was broadly unchanged, averaging +0.01 volatility points to 41.21% across 6M and 1Y.
Skew
RR25 was broadly unchanged, averaging -0.05 volatility points to -4.60% across the six available headline tenors.
Convexity
BF25 was broadly unchanged, averaging +0.04 volatility points to 2.20% across the six available headline tenors.
Largest standard-tenor move
The largest standard-tenor ATM IV move was +0.41 volatility points at 1M, to 33.39%.
Universe roll: added 5AUG26; removed 1AUG26. Comparisons use common expiries only.
05 · Standard-tenor ranking
Largest surface events
01
Largest eligible smile rotation
14AUG26, +1.58 vol pts02
Largest standard-tenor ATM IV move
1M, +0.41 vol pts03
Largest standard-tenor RR25 move
6M, -0.41 vol pts04
Largest standard-tenor BF25 move
1Y, -0.21 vol pts05
Largest eligible SVI sigma move
25JUN27, +0.2088 param06
Largest eligible SVI rho move
4AUG26, -0.0825 param
06 · ATM volatility
Standard-tenor ATM implied volatility.
Tenor
Current (vol %)
Previous (vol %)
Change (vol pts)
Relative change
1W
31.65
31.67
-0.02 vol pts
-0.06%
2W
32.08
32.10
-0.02 vol pts
-0.06%
1M
33.39
32.98
+0.41 vol pts
+1.24%
3M
37.02
37.08
-0.06 vol pts
-0.16%
6M
40.09
40.16
-0.07 vol pts
-0.17%
9M
41.37
41.37
0.00 vol pts
0.00%
1Y
42.33
42.23
+0.10 vol pts
+0.24%
07 · Risk reversals
RR25 skew moved most at 6M.
RR25 was broadly unchanged, averaging -0.05 volatility points to -4.60% across the six available headline tenors. Negative RR25 denotes a richer 25-delta put wing under the call-minus-put convention.
CurrentPrevious day
Tenor
Current (vol %)
Previous (vol %)
Change (vol pts)
1W
-3.90
-4.07
+0.17 vol pts
2W
-4.48
-4.80
+0.32 vol pts
1M
-5.17
-5.11
-0.06 vol pts
3M
-5.28
-4.95
-0.33 vol pts
6M
-4.85
-4.44
-0.41 vol pts
9M
-4.44
-4.21
-0.23 vol pts
1Y
-3.95
-3.96
+0.01 vol pts
08 · Butterflies
BF25 convexity changed most at 1Y.
BF25 was broadly unchanged, averaging +0.04 volatility points to 2.20% across the six available headline tenors. BF25 measures the average 25-delta wing premium over ATM IV.
CurrentPrevious day
Tenor
Current (vol %)
Previous (vol %)
Change (vol pts)
1W
1.84
1.65
+0.19 vol pts
2W
1.92
1.72
+0.20 vol pts
1M
2.07
2.11
-0.04 vol pts
3M
2.24
2.17
+0.07 vol pts
6M
2.63
2.60
+0.03 vol pts
9M
2.62
2.65
-0.03 vol pts
1Y
2.51
2.72
-0.21 vol pts
09 · Expiry effects
Near-settlement moves, shown with context.
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.
0.8d
ATM IV change
2AUG26, -8.82 vol pts1.8d
ATM IV change
3AUG26, -3.60 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.
CurrentPrevious day
Expiry
Time left
Forward now (USD)
Forward change (USD)
ATM IV now
ATM IV change
RR25 change
BF25 change
2AUG26Expiry effect
0.8 days
63,026.75
-557.17 USD
17.81%
-8.82 vol pts
-0.45 vol pts
-0.13 vol pts
3AUG26Expiry effect
1.8 days
63,038.25
-553.25 USD
22.78%
-3.60 vol pts
+0.06 vol pts
0.00 vol pts
4AUG26
2.8 days
63,045.31
-553.77 USD
27.53%
-1.12 vol pts
+0.34 vol pts
-0.16 vol pts
7AUG26
5.8 days
63,067.77
-554.04 USD
31.52%
-0.12 vol pts
+0.30 vol pts
+0.16 vol pts
14AUG26
12.8 days
63,115.85
-552.66 USD
31.91%
-0.15 vol pts
+0.50 vol pts
+0.18 vol pts
21AUG26
19.8 days
63,167.51
-560.40 USD
32.59%
-0.18 vol pts
-0.16 vol pts
+0.28 vol pts
28AUG26
26.8 days
63,219.16
-567.36 USD
32.96%
+0.34 vol pts
+0.04 vol pts
-0.06 vol pts
25SEP26
54.8 days
63,430.87
-571.18 USD
34.96%
+0.01 vol pts
-0.40 vol pts
-0.14 vol pts
30OCT26
89.8 days
63,664.39
-591.33 USD
36.93%
-0.13 vol pts
-0.34 vol pts
+0.06 vol pts
25DEC26
145.8 days
64,067.01
-589.74 USD
39.34%
-0.10 vol pts
-0.47 vol pts
-0.03 vol pts
26MAR27
236.8 days
64,724.53
-597.03 USD
40.78%
-0.07 vol pts
-0.37 vol pts
+0.07 vol pts
25JUN27
327.8 days
65,370.81
-607.69 USD
42.01%
+0.06 vol pts
-0.07 vol pts
-0.15 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.
2AUG26rotation towards puts · wing steepening3AUG26rotation towards puts · wing steepening4AUG26rotation towards puts · wing steepening7AUG26rotation towards calls · wing steepening14AUG26rotation towards calls · wing steepening21AUG26wing steepening28AUG26parallel shift higher25SEP26rotation towards puts30OCT26limited movement25DEC26limited movement26MAR27limited movement25JUN27parallel shift higher
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
2AUG26
3AUG26
4AUG26
7AUG26
14AUG26
21AUG26
28AUG26
25SEP26
30OCT26
25DEC26
26MAR27
25JUN27
-0.30kATM+0.30k
12 · Technical appendix
Model parameters and normalized Greeks.
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 4AUG26; the largest sigma change occurred at 25JUN27.
Expiry
Δ a
Δ b
Δ rho
Δ m
Δ sigma
Smile classification
2AUG26
-0.01700
+0.02030
+0.02360
+0.00940
+0.03590
rotation towards puts, wing steepening
3AUG26
-0.02500
+0.02830
-0.03430
-0.04020
+0.08820
rotation towards puts, wing steepening
4AUG26
-0.03700
+0.03530
-0.08250
-0.08270
+0.19550
rotation towards puts, wing steepening
7AUG26
-0.03860
+0.04540
+0.00650
-0.02430
+0.15200
rotation towards calls, wing steepening
14AUG26
-0.03930
+0.04330
+0.07730
+0.01960
+0.12180
rotation towards calls, wing steepening
21AUG26
-0.00600
+0.01700
+0.04230
+0.01460
-0.03800
wing steepening
28AUG26
-0.02380
+0.01880
+0.05020
+0.03230
+0.08670
parallel shift higher
25SEP26
-0.05130
+0.03550
-0.02170
-0.01150
+0.17700
rotation towards puts
30OCT26
-0.06280
+0.04370
-0.05310
-0.04500
+0.19080
limited movement
25DEC26
-0.09350
+0.06010
-0.00810
-0.07600
+0.18260
limited movement
26MAR27
-0.05230
+0.02860
+0.02800
+0.00170
+0.09030
limited movement
25JUN27
-0.10820
+0.06580
-0.03510
-0.14230
+0.20880
parallel shift higher
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.
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.
