BELFB · IV Rank History

Bel Fuse Inc

IV rank shows where BELFB's implied volatility sits within its own recent range: 0 is the lowest reading in the window, 100 the highest. This page gives the 52-week version, the 90-session version our screeners use, the IV percentile, and the daily history.

BELFB's 30-day at-the-money implied volatility was 57.1% as of Oct 5, 2026. Its 52-week IV rank is 60 and its IV percentile is 74%: IV was lower on 74% of the past year's sessions. Over those 52 weeks it ranged from 35.9% (Dec 19, 2025) to 71.3% (Jul 22, 2026). On the 90-session window our screeners use, the IV rank is 40.

BELFB IV rank history

504 sessions

Filled line: 90-session IV rank (0–100, left axis). Dashed line: 30-day at-the-money implied volatility (right axis).

BELFB IV rank and implied volatility as of 2026-10-05

52-Week IV Rank
60
0 = year low, 100 = year high
IV Percentile
74%
of past-year sessions had lower IV
90-Session IV Rank
40
used by our screeners
30-Day ATM IV
57.1%
1-year average 52.6%
7-Day ATM IV
48.7%
90-session rank 19
52-Week IV High
71.3%
2026-07-22
52-Week IV Low
35.9%
2025-12-19
History Since
2023-05-02
834 sessions

How these are measured. Implied volatility here is BELFB's 30-day at-the-money IV: the implied volatility of the calls and puts struck nearest the share price, blended between the expirations on either side of 30 days so every reading covers the same horizon. It's the IV level options traders usually quote, and it doesn't jump when the nearest expiration rolls from a weekly to a monthly. The 7-day figure is the same measure a week out, so it reacts first to near-term events such as earnings.

52-week IV rank = (today's IV − 52-week low) ÷ (52-week high − 52-week low) × 100. IV percentile is the share of the past year's sessions that closed with lower IV than today. The 90-session IV rank applies the same rank formula to the last 90 sessions, so it reacts faster.

A high reading means BELFB options are expensive relative to their own recent history, which is common ahead of earnings or after a sharp move. It says nothing about which way the stock will go. The Vol Arb Screener ranks every tracked symbol by these measures.

BELFB implied volatility by month

MonthAvg ATM IVHighLowAvg IV Rank (90-session)
Oct 2026 (to date) 56.2% 57.1% 54.8% 36
Sep 2026 53.0% 55.8% 49.4% 26
Aug 2026 52.0% 57.4% 48.6% 24
Jul 2026 63.3% 71.3% 54.3% 70
Jun 2026 51.5% 54.0% 47.7% 23
May 2026 48.1% 49.9% 46.1% 16
Apr 2026 60.9% 69.3% 47.6% 73
Mar 2026 60.1% 70.2% 55.0% 78
Feb 2026 58.6% 66.7% 54.4% 85
Jan 2026 49.7% 54.7% 43.5% 69
Dec 2025 39.7% 42.8% 35.9% 10
Nov 2025 43.8% 50.7% 39.4% 32
Oct 2025 50.0% 55.8% 39.9% 83
Sep 2025 42.8% 48.1% 39.9% 69
Aug 2025 42.5% 45.7% 39.5% 29
Jul 2025 42.6% 46.8% 36.2% 27
Jun 2025 35.3% 40.0% 30.6% 8
May 2025 39.1% 48.9% 32.4% 13
Apr 2025 60.1% 74.6% 47.5% 75
Mar 2025 44.4% 51.1% 41.3% 62
Feb 2025 41.0% 44.5% 36.9% 40
Jan 2025 45.3% 50.4% 40.3% 66
Dec 2024 38.5% 45.0% 34.4% 34
Nov 2024 37.6% 43.4% 32.7% 29
Oct 2024 46.7% 53.7% 38.8% 60
Sep 2024 40.3% 48.0% 29.3% 29
Aug 2024 46.8% 58.3% 38.1% 45
Jul 2024 48.5% 55.6% 40.7% 55
Jun 2024 39.7% 44.3% 36.0% 33
May 2024 38.5% 47.1% 32.9% 30
Apr 2024 55.6% 66.1% 38.9% 78
Mar 2024 43.0% 52.0% 26.9% 38
Feb 2024 50.9% 62.6% 36.2% 42
Jan 2024 48.3% 53.0% 41.5% 36
Dec 2023 39.5% 46.4% 33.2% 17
Nov 2023 39.6% 48.5% 32.0% 13
Oct 2023 59.2% 76.7% 40.8% 71
Sep 2023 48.6% 55.3% 38.2% 50
Aug 2023 48.4% 55.4% 41.9% 50
Jul 2023 53.1% 64.7% 42.6% 68
Jun 2023 43.1% 52.3% 32.2% 26
May 2023 50.7% 61.6% 42.3% 29

BELFB IV rank: last 30 sessions

DateIV Rank (90-session)30-Day ATM IV7-Day ATM IV
2026-10-05 40 57.1% 48.7%
2026-10-02 30 54.8% 46.8%
2026-10-01 38 56.6% 50.7%
2026-09-30 33 55.5% 50.4%
2026-09-29 33 55.4% 50.3%
2026-09-28 31 55.1% 50.8%
2026-09-25 20 52.5% 47.9%
2026-09-24 28 54.3% —
2026-09-23 23 53.1% —
2026-09-22 29 54.4% —
2026-09-21 30 54.6% —
2026-09-18 14 50.4% —
2026-09-17 13 49.4% —
2026-09-16 27 52.8% 74.4%
2026-09-15 29 53.3% 75.2%
2026-09-14 22 51.5% 59.4%
2026-09-11 20 51.2% 49.9%
2026-09-10 30 53.5% 54.7%
2026-09-09 29 53.4% 54.3%
2026-09-08 39 55.8% 55.3%
2026-09-04 19 50.8% 50.3%
2026-09-03 25 52.3% 51.6%
2026-09-02 24 52.2% 52.8%
2026-09-01 19 50.8% 47.0%
2026-08-31 25 52.5% 51.1%
2026-08-28 10 48.6% 45.1%
2026-08-27 15 49.9% —
2026-08-26 18 50.5% —
2026-08-25 25 52.4% —
2026-08-24 28 53.0% —

Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.