Which C-clamp Brand Wins?
This head-to-head test of 18 c-clamp options has the measured results for each. See how they ranked and watch the full test video.
Irwin
Price shown in test: $14
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The quick take
The short version of why each pick lands where it does, built straight from the measured results.
Best in 1 of 8 measurements, including Swivel Head Torque At 500 Lb Load.
The measured results
Every number below is read straight from the test. Products are listed in the order they finished.
Weight
- 1Wilton heavy duty (high visibility)18.77 lb
more than three times any other brand
- 2Wright Tool4.97 lb
- 3Stanley Proto5.1 lb
- 4Crescent4.59 lb
- 5Yostjust over5 lb
heaviest yet at that point in testing
- 6Wilton 6 FC (standard)5.59 lb
- 7Kanka3.88 lb
- 8Harden2.55 lb
- 9Bessey C-Clamp2.79 lb
- 10Performance Tool2.63 lb
- 11Groz
very close to 3 lb
- 12Irwin3.73 lb
heaviest yet at that point in testing
- 13WEN2.85 lb
- 14Lincoln Electric2.35 lb
- 15Pony2.31 lb
described as pretty light
- 16Pittsburgh2.44 lb
- 17Bessey F-Style2.32 lb
very light
- 18Shop-Tek1.89 lb
Jaw Opening
- 1Wilton heavy duty (high visibility)close to6.5 in
- 2Wright Tooljust over6 in
- 3Stanley Protoclose to6 in
- 4Crescentclose to6.5 in
- 5Yostclose to6.25 in
- 6Wilton 6 FC (standard)close to6.25 in
- 7Kankaright at6 in
- 8Hardenclose to6.25 in
- 9Bessey C-Clampclose to6.25 in
- 10Performance Toolclose to6.5 in
- 11Grozjust under6 in
- 12Irwin6.875 in
- 13WEN6.4375 in
- 14Lincoln Electricclose to6 in
- 15Ponyclose to6.5 in
- 16Pittsburgh6.4375 in
- 17Bessey F-Styleclose to7 in
largest of all brands
- 18Shop-Tek5.625 in
actual vs 6 in advertised capacity
Throat
- 1Wilton heavy duty (high visibility)3.5 in
- 2Wright Toolclose to4.2 in
- 3Stanley Protoclose to4.2 in
- 4Crescentclose to4.2 in
- 5Yost4.25 in
deepest yet at that point
- 6Wilton 6 FC (standard)4.25 in
second deepest yet at that point
- 7Kanka2.75 in
- 8Harden2.75 in
- 9Bessey C-Clamp2.75 in
- 10Performance Tool2.5 in
- 11Groz
very close to 3 in
- 12Irwin3.5 in
most yet at that point
- 13WEN2.75 in
- 14Lincoln Electric2.75 in
- 15Pony3.5 in
same as Irwin
- 16Pittsburgh2.75 in
half an inch more than the Shop-Tek
- 17Bessey F-Style4.6 in
deepest of all brands
- 18Shop-Tek2.25 in
weakest throat reach of all brands tested
Adjustment Screw Slop
- 1Wilton heavy duty (high visibility)0.0385 in
- 2Wright Tool0.073 in
- 3Stanley Proto0.024 in2nd
second best (least slop) of all brands
- 4Crescent0.112 in
- 5Yost0.035 in
least slop yet at that point
- 6Wilton 6 FC (standard)0.067 in
- 7Kanka0.0215 in
the least slop (best) of all brands tested
- 8Harden0.14 in
about the same as Pittsburgh
- 9Bessey C-Clamp0.24 in
quite a bit of slop
- 10Performance Tool0.332 in
about twice as much slop as any other brand tested
- 11Groz0.074 in
better than most other brands
- 12Irwin0.06 in
least yet at that point
- 13WEN0.187 in
the most slop yet at that point in testing
- 14Lincoln Electric0.194 in
- 15Pony0.118 in
about the same as Pittsburgh and Harden
- 16Pittsburgh0.12 in
a little worse than Shop-Tek
- 17Bessey F-Style0.055 in
better than average
- 18Shop-Tek0.095 in
Clamping Force 50 Inlb Torque
- 1Wilton heavy duty (high visibility)1,039 lb
before the torque wrench clicked off (test capped, not a true failure point)
- 2Wright Tool667 lb
- 3Stanley Proto673 lb
- 4Crescent831 lb
about 200 lb better than average; coarse threads held it back
- 5Yost616 lb
held back by very coarse threads despite a longer than average handle
- 6Wilton 6 FC (standard)747 lb
despite coarser threads than most other brands
- 7Kanka616 lb
about the same as Yost
- 8Harden638 lb
very close to Pittsburgh's result
- 9Bessey C-Clamp856 lb
about 214 lb less than the Groz
- 10Performance Tool282 lb
the worst result of all 18 clamps at that point
- 11Groz1,070 lb
the highest of all 18 clamps in this standardized test, took the lead from the WEN
- 12Irwin1,005 lb4th
fourth best in the standardized test, moved into second place behind WEN at the time
- 13WEN1,058 lb2nd
second best of all 18 clamps, almost twice the Pittsburgh's result
- 14Lincoln Electric770 lb3rd
third place at that point in testing, behind Irwin
- 15Pony651 lb
a little better than Pittsburgh
- 16Pittsburgh644 lb
close to 250 lb more than the Shop-Tek
- 17Bessey F-Style
just fell short of 600 lb
- 18Shop-Tek396 lb
weakest of all 18 clamps
Swivel Head Torque At 500 Lb Load
- 1Wilton heavy duty (high visibility)
not tested, this clamp has no swivel head
- 2Wright Tool8 in lb
the most efficient (lowest friction) swivel head of any brand tested
- 3Stanley Proto12 in lb
tied with Crescent
- 4Crescent12 in lb
tied with Stanley Proto
- 5Yost16 in lb
tied with Lincoln Electric
- 6Wilton 6 FC (standard)17 in lb
same as Kanka, 9 in lb more than the Wright Tool
- 7Kanka17 in lb
about the same as Wilton (6 FC)
- 8Harden48 in lb
over four times more resistance than the Irwin
- 9Bessey C-Clamp18 in lb
almost as good as Lincoln Electric and Yost
- 10Performance Tool25 in lb
better than Pony but still more than twice the Irwin's result
- 11Groz14 in lb
better than Lincoln Electric and Yost
- 12Irwin11 in lb
best yet at that point in testing
- 13WEN23 in lb
about half the resistance of the Pittsburgh, called good performance for a budget clamp
- 14Lincoln Electric16 in lb2nd
second best at that point in testing
- 15Pony36 in lb
about three times the Irwin's result, described as pretty stiff
- 16Pittsburgh45 in lb
- 17Bessey F-Style15 in lb
moves very freely
- 18Shop-Tek
swivel head was stuck solid and could not be tested; too flat to grip with locking pliers to attempt the measurement
Handle Bend Test
- 1Wilton heavy duty (high visibility)
no handle, tested with a ratchet and socket instead
- 2Wright Tooljust over9,000 lb
before the frame began to twist, frame not bent, adjusting screw still in great shape
- 3Stanley Protoalmost9,000 lb
before threads galled, making the clamp very difficult to work
- 4Crescentjust over5,700 lb
took the lead at that point in testing, but threads became galled and difficult to work
- 5Yostover5,300 lb
by far the best yet at that point; handle was the first part to give, frame not bent
- 6Wilton 6 FC (standard)almost6,400 lb
about 3,600 lb less than the Wright Tool
- 7Kanka4,354 lb2nd
second place at that point, frame with a small bend
- 8Harden1,537 lb
handle badly bent; presenter notes it costs the same as the Irwin but delivers about half the performance
- 9Bessey C-Clamp3,625 lb
frame began to bend
- 10Performance Tool1,416 lb
handle bent
- 11Groz3,669 lb
frame began to twist
- 12Irwin3,321 lb
handle bent but frame and adjusting screw still in good shape
- 13WEN2,568 lb
small frame bend, outperformed the Pittsburgh
- 14Lincoln Electric1,681 lb
frame began to twist
- 15Pony1,562 lb
frame beginning to bend
- 16Pittsburgh
briefly reached 2,163 lb before losing ground, small frame bend
- 17Bessey F-Style
rated by its own packaging for 1,330 lb; actually reached 1,615 lb, better than advertised, with only a very small frame bend
- 18Shop-Tek812 lb
before the handle bent, weakest of all brands
Failure Load
- 1Wilton heavy duty (high visibility)
rated for 27,500 lb; a 20-ton (40,000 lb) hydraulic ram was exceeded and the clamp was still only stretching, not bending or breaking, finally reaching 50,327 lb (recap rounds to 'over 50,000 lb') with no damage, more than three times the second place finisher
- 2Wright Tooljust over11,300 lb
(recap: 'over 11,000 lb'), frame experienced a small bend; presenter notes it outperformed the field throughout the showdown
- 3Stanley Protoover11,000 lb
(recap figure; individual mention says 'almost 9,000' at the handle-bend stage but the separate final failure test reached over 11,000 lb), frame experienced a pretty bad bend
- 4Crescentjust over10,000 lb
extremely durable, frame experienced a bend
- 5Yostalmost10,000 lb
refused to break; unlike other brands, the frame returned to its original shape once tension was removed rather than holding a permanent bend, an unusually elastic result
- 6Wilton 6 FC (standard)just over9,200 lb
frame and adjusting screw now bent
- 7Kankaalmost6,000 lb
frame twisted and bent
- 8Hardenover5,200 lb
frame badly bent but did not crack
- 9Bessey C-Clampalmost5,000 lb
after a couple of attempts, frame experienced a really bad bend
- 10Performance Toolalmost4,200 lb
frame and adjustment screw badly bent
- 11Grozjust over4,000 lb
before suddenly snapping
- 12Irwinjust under3,900 lb
- 13WEN
described as breaking into almost 4,000 lb, with the frame beginning to bend and twist at 3,500 lb; exact final failure figure is somewhat ambiguous in the transcript phrasing, kept as 'just under 4,000 lb'
- 14Lincoln Electricalmost3,200 lb
- 15Pony2,765 lb
frame snapped
- 16Pittsburgh2,581 lb
when the frame broke, described as 'pretty brutal' cast metal failure
- 17Bessey F-Stylejust over2,000 lb
frame began to twist and bend
- 18Shop-Tek980 lb
frame bent in two different directions, first brand to fail
How it was tested
- standardized maximum clamping force at 50 in lb of handle torque
- physical measurements: jaw opening, throat depth, adjustment screw slop, weight
- swivel head friction/rotation resistance under a 500 lb clamping load
- handle bending force (maximum force before the handle bends, using a cheater bar)
- ultimate failure load (maximum holding force before frame or screw damage/breakage)
“So which C-clamp is the best? If it's all about brute force the heavy duty Wilton is in a league of its own, in my opinion it's way too large, heavy and expensive for most applications. The Stanley Proto and Wright Tool both performed extremely well but both of them fall within the buy once and cry once category when it comes to price. And it's all about affordability I really like the Irwin at only 14, it performed extremely well.”
