BELFB · Bel Fuse Inc /Nj

Track BELFB — free

$262.43 -1.44 (-0.55%) At close · Aug 20

Market Cap

$3.15B

14.44M

Options Chain

Underlying $262.43 · at close Aug 20, 2026 Options Calculator

Positioning

Aug 21, 2026 · expires today · 64 contracts · mixed snapshot sessions · Jun 25, 2026–Aug 19, 2026; 44 unknown

Put / call OI

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dated and unknown snapshot sessions

Open interest

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dated and unknown snapshot sessions

Volume

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dated and unknown snapshot sessions

Chain

Click any strike for greeks, breakeven and the calculator

Expiry

Aug 21 0d Sep 18 28d Oct 16 56d Dec 18 119d Jan 15 147d Mar 19 210d

Calls						Puts
OI	Vol	IV	Δ	Last	Strike	Last	Δ	IV	Vol	OI
0	—	—	—	—		—	-0.037	655.4%	—	0
Call · $175 In the money Snapshot session Unknown Last — Breakeven — Implied vol — Delta — Gamma — Theta — Vega — Open interest 0 Model this call Put · $175 Snapshot session Unknown Last — Breakeven — Implied vol 655.4% Delta -0.037 ≈4% ITM Gamma 0.001 Theta -4.938 Vega 0.009 Open interest 0 Model this put
0	—	—	—	—		—	-0.033	590.4%	—	0
Call · $180 In the money Snapshot session Unknown Last — Breakeven — Implied vol — Delta — Gamma — Theta — Vega — Open interest 0 Model this call Put · $180 Snapshot session Unknown Last — Breakeven — Implied vol 590.4% Delta -0.033 ≈3% ITM Gamma 0.001 Theta -4.048 Vega 0.009 Open interest 0 Model this put
0	—	—	—	—		—	-0.059	665.9%	—	0
Call · $185 In the money Snapshot session Unknown Last — Breakeven — Implied vol — Delta — Gamma — Theta — Vega — Open interest 0 Model this call Put · $185 Snapshot session Unknown Last — Breakeven — Implied vol 665.9% Delta -0.059 ≈6% ITM Gamma 0.002 Theta -7.415 Vega 0.015 Open interest 0 Model this put
0	—	—	—	—		—	-0.036	515.8%	—	0
Call · $190 In the money Snapshot session Unknown Last — Breakeven — Implied vol — Delta — Gamma — Theta — Vega — Open interest 0 Model this call Put · $190 Snapshot session Unknown Last — Breakeven — Implied vol 515.8% Delta -0.036 ≈4% ITM Gamma 0.001 Theta -3.766 Vega 0.009 Open interest 0 Model this put
0	—	—	—	—		—	-0.045	510%	—	0
Call · $195 In the money Snapshot session Unknown Last — Breakeven — Implied vol — Delta — Gamma — Theta — Vega — Open interest 0 Model this call Put · $195 Snapshot session Unknown Last — Breakeven — Implied vol 510% Delta -0.045 ≈5% ITM Gamma 0.002 Theta -4.543 Vega 0.009 Open interest 0 Model this put
0	—	—	—	—		$0.80	-0.04	450.4%	1	1
Call · $200 In the money Snapshot session Unknown Last — Breakeven — Implied vol — Delta — Gamma — Theta — Vega — Open interest 0 Model this call Put · $200 Snapshot session Jul 31, 2026 Last $0.80 Breakeven $199.20 Implied vol 450.4% Delta -0.04 ≈4% ITM Gamma 0.002 Theta -3.65 Vega 0.009 Open interest 1 Model this put
0	—	—	—	—		—	-0.046	388.3%	—	0
Call · $210 In the money Snapshot session Unknown Last — Breakeven — Implied vol — Delta — Gamma — Theta — Vega — Open interest 0 Model this call Put · $210 Snapshot session Unknown Last — Breakeven — Implied vol 388.3% Delta -0.046 ≈5% ITM Gamma 0.002 Theta -3.533 Vega 0.01 Open interest 0 Model this put
2	4	—	—	$38.00		$5.90	-0.073	364.6%	1	2
Call · $220 In the money Snapshot session Jul 28, 2026 Last $38.00 Breakeven $258.00 Implied vol — Delta — Gamma — Theta — Vega — Open interest 2 Model this call Put · $220 Snapshot session Jul 27, 2026 Last $5.90 Breakeven $214.10 Implied vol 364.6% Delta -0.073 ≈7% ITM Gamma 0.004 Theta -4.731 Vega 0.017 Open interest 2 Model this put
0	2	—	—	$28.50		$1.20	-0.182	480%	1	1
Call · $230 In the money Snapshot session Jul 29, 2026 Last $28.50 Breakeven $258.50 Implied vol — Delta — Gamma — Theta — Vega — Open interest 0 Model this call Put · $230 Snapshot session Aug 7, 2026 Last $1.20 Breakeven $228.80 Implied vol 480% Delta -0.182 ≈18% ITM Gamma 0.005 Theta -11.99 Vega 0.026 Open interest 1 Model this put
4	4	—	—	$71.00		$9.87	-0.1	227.2%	1	2
Call · $240 In the money Snapshot session Jun 29, 2026 Last $71.00 Breakeven $311.00 Implied vol — Delta — Gamma — Theta — Vega — Open interest 4 Model this call Put · $240 Snapshot session Jul 9, 2026 Last $9.87 Breakeven $230.13 Implied vol 227.2% Delta -0.1 ≈10% ITM Gamma 0.007 Theta -3.74 Vega 0.018 Open interest 2 Model this put
2	1	—	—	$22.37		—	-0.105	144.7%	—	0
Call · $250 In the money Snapshot session Aug 3, 2026 Last $22.37 Breakeven $272.37 Implied vol — Delta — Gamma — Theta — Vega — Open interest 2 Model this call Put · $250 Snapshot session Unknown Last — Breakeven — Implied vol 144.7% Delta -0.105 ≈11% ITM Gamma 0.012 Theta -2.472 Vega 0.018 Open interest 0 Model this put
0	—	—	—	—		$12.00	-0.337	204.6%	1	4
Call · $260 In the money Snapshot session Unknown Last — Breakeven — Implied vol — Delta — Gamma — Theta — Vega — Open interest 0 Model this call Put · $260 Snapshot session Jul 22, 2026 Last $12.00 Breakeven $248.00 Implied vol 204.6% Delta -0.337 ≈34% ITM Gamma 0.017 Theta -7.119 Vega 0.036 Open interest 4 Model this put
Underlying $262.43
5	5	73.4%	0.404	$21.08		—	-0.522	199.3%	—	0
Call · $270 Snapshot session Jul 17, 2026 Last $21.08 Breakeven $291.08 Implied vol 73.4% Delta 0.404 ≈40% ITM Gamma 0.05 Theta -2.689 Vega 0.042 Open interest 5 Model this call Put · $270 In the money Snapshot session Unknown Last — Breakeven — Implied vol 199.3% Delta -0.522 ≈52% ITM Gamma 0.019 Theta -7.479 Vega 0.042 Open interest 0 Model this put
52	1	107.4%	0.153	$21.00		—	-0.642	268%	—	0
Call · $280 Snapshot session Aug 4, 2026 Last $21.00 Breakeven $301.00 Implied vol 107.4% Delta 0.153 ≈15% ITM Gamma 0.021 Theta -2.4 Vega 0.029 Open interest 52 Model this call Put · $280 In the money Snapshot session Unknown Last — Breakeven — Implied vol 268% Delta -0.642 ≈64% ITM Gamma 0.013 Theta -9.471 Vega 0.037 Open interest 0 Model this put
10	20	274.4%	0.246	$34.18		$24.00	-0.693	348.2%	3	3
Call · $290 Snapshot session Jun 25, 2026 Last $34.18 Breakeven $324.18 Implied vol 274.4% Delta 0.246 ≈25% ITM Gamma 0.011 Theta -8.251 Vega 0.038 Open interest 10 Model this call Put · $290 In the money Snapshot session Jul 23, 2026 Last $24.00 Breakeven $266.00 Implied vol 348.2% Delta -0.693 ≈69% ITM Gamma 0.01 Theta -11.457 Vega 0.038 Open interest 3 Model this put
15	3	376.7%	0.244	$0.70		—	-0.732	412.8%	—	0
Call · $300 Snapshot session Aug 19, 2026 Last $0.70 Breakeven $300.70 Implied vol 376.7% Delta 0.244 ≈24% ITM Gamma 0.008 Theta -11.224 Vega 0.03 Open interest 15 Model this call Put · $300 In the money Snapshot session Unknown Last — Breakeven — Implied vol 412.8% Delta -0.732 ≈73% ITM Gamma 0.008 Theta -12.863 Vega 0.039 Open interest 0 Model this put
1	1	284.8%	0.107	$8.70		—	-0.758	469.2%	—	0
Call · $310 Snapshot session Jul 24, 2026 Last $8.70 Breakeven $318.70 Implied vol 284.8% Delta 0.107 ≈11% ITM Gamma 0.006 Theta -4.902 Vega 0.02 Open interest 1 Model this call Put · $310 In the money Snapshot session Unknown Last — Breakeven — Implied vol 469.2% Delta -0.758 ≈76% ITM Gamma 0.006 Theta -13.84 Vega 0.03 Open interest 0 Model this put
26	5	339.2%	0.103	$7.80		—	-0.774	525.9%	—	0
Call · $320 Snapshot session Aug 4, 2026 Last $7.80 Breakeven $327.80 Implied vol 339.2% Delta 0.103 ≈10% ITM Gamma 0.005 Theta -5.694 Vega 0.02 Open interest 26 Model this call Put · $320 In the money Snapshot session Unknown Last — Breakeven — Implied vol 525.9% Delta -0.774 ≈77% ITM Gamma 0.005 Theta -14.837 Vega 0.03 Open interest 0 Model this put
3	1	322.1%	0.057	$0.40		—	-0.787	579.4%	—	0
Call · $330 Snapshot session Jul 30, 2026 Last $0.40 Breakeven $330.40 Implied vol 322.1% Delta 0.057 ≈6% ITM Gamma 0.003 Theta -3.418 Vega 0.012 Open interest 3 Model this call Put · $330 In the money Snapshot session Unknown Last — Breakeven — Implied vol 579.4% Delta -0.787 ≈79% ITM Gamma 0.005 Theta -15.749 Vega 0.031 Open interest 0 Model this put
0	—	370.1%	0.059	—		—	-0.802	621.7%	—	0
Call · $340 Snapshot session Unknown Last — Breakeven — Implied vol 370.1% Delta 0.059 ≈6% ITM Gamma 0.003 Theta -4.037 Vega 0.012 Open interest 0 Model this call Put · $340 In the money Snapshot session Unknown Last — Breakeven — Implied vol 621.7% Delta -0.802 ≈80% ITM Gamma 0.004 Theta -16.169 Vega 0.031 Open interest 0 Model this put
4	3	408.6%	0.056	$0.50		—	-0.813	667.5%	—	0
Call · $350 Snapshot session Aug 17, 2026 Last $0.50 Breakeven $350.50 Implied vol 408.6% Delta 0.056 ≈6% ITM Gamma 0.003 Theta -4.322 Vega 0.012 Open interest 4 Model this call Put · $350 In the money Snapshot session Unknown Last — Breakeven — Implied vol 667.5% Delta -0.813 ≈81% ITM Gamma 0.004 Theta -16.83 Vega 0.032 Open interest 0 Model this put
0	—	430.1%	0.047	—		—	-0.82	715.2%	—	0
Call · $360 Snapshot session Unknown Last — Breakeven — Implied vol 430.1% Delta 0.047 ≈5% ITM Gamma 0.002 Theta -3.939 Vega 0.012 Open interest 0 Model this call Put · $360 In the money Snapshot session Unknown Last — Breakeven — Implied vol 715.2% Delta -0.82 ≈82% ITM Gamma 0.004 Theta -17.652 Vega 0.032 Open interest 0 Model this put
1	1	466.7%	0.046	$11.70		—	-0.825	764.7%	—	0
Call · $370 Snapshot session Jul 1, 2026 Last $11.70 Breakeven $381.70 Implied vol 466.7% Delta 0.046 ≈5% ITM Gamma 0.002 Theta -4.223 Vega 0.013 Open interest 1 Model this call Put · $370 In the money Snapshot session Unknown Last — Breakeven — Implied vol 764.7% Delta -0.825 ≈83% ITM Gamma 0.003 Theta -18.633 Vega 0.032 Open interest 0 Model this put
0	—	494.6%	0.042	—		—	-0.827	817.6%	—	0
Call · $380 Snapshot session Unknown Last — Breakeven — Implied vol 494.6% Delta 0.042 ≈4% ITM Gamma 0.002 Theta -4.173 Vega 0.013 Open interest 0 Model this call Put · $380 In the money Snapshot session Unknown Last — Breakeven — Implied vol 817.6% Delta -0.827 ≈83% ITM Gamma 0.003 Theta -19.853 Vega 0.033 Open interest 0 Model this put
0	—	541.1%	0.047	—		—	-0.836	844.1%	—	0
Call · $390 Snapshot session Unknown Last — Breakeven — Implied vol 541.1% Delta 0.047 ≈5% ITM Gamma 0.002 Theta -4.957 Vega 0.013 Open interest 0 Model this call Put · $390 In the money Snapshot session Unknown Last — Breakeven — Implied vol 844.1% Delta -0.836 ≈84% ITM Gamma 0.003 Theta -19.769 Vega 0.022 Open interest 0 Model this put
0	—	547.4%	0.037	—		—	-0.844	866%	—	0
Call · $400 Snapshot session Unknown Last — Breakeven — Implied vol 547.4% Delta 0.037 ≈4% ITM Gamma 0.001 Theta -4.164 Vega 0.007 Open interest 0 Model this call Put · $400 In the money Snapshot session Unknown Last — Breakeven — Implied vol 866% Delta -0.844 ≈84% ITM Gamma 0.003 Theta -19.483 Vega 0.022 Open interest 0 Model this put
0	—	833%	0.129	—		—	-0.848	898.3%	—	0
Call · $410 Snapshot session Unknown Last — Breakeven — Implied vol 833% Delta 0.129 ≈13% ITM Gamma 0.002 Theta -16.338 Vega 0.023 Open interest 0 Model this call Put · $410 In the money Snapshot session Unknown Last — Breakeven — Implied vol 898.3% Delta -0.848 ≈85% ITM Gamma 0.002 Theta -19.783 Vega 0.023 Open interest 0 Model this put
0	—	596.4%	0.034	—		—	-0.852	932.1%	—	0
Call · $420 Snapshot session Unknown Last — Breakeven — Implied vol 596.4% Delta 0.034 ≈3% ITM Gamma 0.001 Theta -4.24 Vega 0.007 Open interest 0 Model this call Put · $420 In the money Snapshot session Unknown Last — Breakeven — Implied vol 932.1% Delta -0.852 ≈85% ITM Gamma 0.002 Theta -20.2 Vega 0.023 Open interest 0 Model this put
0	—	827%	0.094	—		—	-0.855	962.9%	—	0
Call · $430 Snapshot session Unknown Last — Breakeven — Implied vol 827% Delta 0.094 ≈9% ITM Gamma 0.002 Theta -13.121 Vega 0.023 Open interest 0 Model this call Put · $430 In the money Snapshot session Unknown Last — Breakeven — Implied vol 962.9% Delta -0.855 ≈86% ITM Gamma 0.002 Theta -20.498 Vega 0.023 Open interest 0 Model this put
0	—	832.6%	0.086	—		—	-0.857	997.4%	—	0
Call · $440 Snapshot session Unknown Last — Breakeven — Implied vol 832.6% Delta 0.086 ≈9% ITM Gamma 0.002 Theta -12.275 Vega 0.014 Open interest 0 Model this call Put · $440 In the money Snapshot session Unknown Last — Breakeven — Implied vol 997.4% Delta -0.857 ≈86% ITM Gamma 0.002 Theta -21.029 Vega 0.023 Open interest 0 Model this put
0	—	828.8%	0.076	—		—	-0.862	1020.6%	—	0
Call · $450 Snapshot session Unknown Last — Breakeven — Implied vol 828.8% Delta 0.076 ≈8% ITM Gamma 0.002 Theta -11.056 Vega 0.014 Open interest 0 Model this call Put · $450 In the money Snapshot session Unknown Last — Breakeven — Implied vol 1020.6% Delta -0.862 ≈86% ITM Gamma 0.002 Theta -20.973 Vega 0.024 Open interest 0 Model this put
0	—	780.3%	0.052	—		$146.00	-0.865	1049.5%	1	0
Call · $460 Snapshot session Unknown Last — Breakeven — Implied vol 780.3% Delta 0.052 ≈5% ITM Gamma 0.001 Theta -7.758 Vega 0.014 Open interest 0 Model this call Put · $460 In the money Snapshot session Jul 2, 2026 Last $146.00 Breakeven $314.00 Implied vol 1049.5% Delta -0.865 ≈86% ITM Gamma 0.002 Theta -21.267 Vega 0.024 Open interest 0 Model this put

About this data

Each contract's last price, volume, greeks, implied volatility and open interest belongs to the snapshot session shown in its details; unknown means the provider omitted the timestamp. This chain has mixed snapshot sessions · Jun 25, 2026–Aug 19, 2026; 44 unknown. Cross-contract positioning totals are shown only when every returned row has the same known session. Bid and ask are not included on this plan.

In-the-money strikes are tinted, deepening toward the money, and the bar beside each open-interest figure scales to the heaviest strike shown. The 24 strikes around the money are shown by default — switch to "All 32" for the wings.

Key facts CIK 729580 CUSIP 077347201 13F (30d) 262 filings 254 filers Visit website Investor relations