Informational Guide

How To Test A Torque Wrench

In this guide, we discuss how to test a torque wrench and give you a DIY calibration guide.

If you are adjusting nuts and bolts, you want to use your torque wrench, but do you know how to test a torque wrench? In this article, we will look closer at how to get a torque wrench calibrated. Instead of wasting time watching how to calibrate a torque wrench videos, follow our simple steps.  

If you want to know how to test a torque wrench for accuracy, you first must understand how the tool is used. While the torque wrench is used to tighten and loosen nuts and bolts, there are different types with various methods of operation. The clicker torque wrench spring rests with some pressure that controls how much torque gets delivered.  

Dial indicator wrenches have a gauge by the handle that shows you how much torque is applied. Electric torque wrenches can be run by a battery or outlet. The settings are applied, and the wrench operates itself to the appropriate torque amount.  

how torque wrenches work

Why Should You Calibrate A Torque Wrench?

Before you learn how to calibrate a torque wrench, you must also consider why you would want to do this. First of all, it's essential that your torque wrench is accurate. The smallest miscalculation can make a big difference. Additionally, torque wrenches should be calibrated every 12 months or 5,000 uses according to the International Organization of Standardization, ISO 6789. 

The torque wrench must also be stored properly, or it could need to be recalibrated. How often do you need to calibrate a torque wrench? If you use it in extreme weather or temperatures, you will need to adjust it more frequently. Above all, if the torque wrench is overworked, it’s imperative that you recalibrate it.  

How Do You Know When A Torque Wrench Needs To Be Calibrated 

If you want to know how to calibrate a torque wrench at home, you must first know when it is time. Here are a few signs to consider.  

  • 12 Months Have Passed Since The Last Calibration  
    As we have already determined, you need to calibrate the torque wrench every 12 months or 5,000 uses, whichever comes first. These are standard guidelines for tool operation.  
  • Visible Signs Of Damage  
    As with any hand tool, you should replace it when damage is noticed. In this case, you wouldn’t just learn how to calibrate a digital torque wrench. Instead, get a new one.  
  • Signs Of Oil On The Exterior  
    However, if there is just oil on the exterior or your measurements seem to be inaccurate, consider calibrating it again. You might be able to continue using it instead of buying a new one. How much does it cost to calibrate a torque wrench? A lot less than buying a new one, especially if you do it yourself. 

How To Calibrate A Torque Wrench (At Home DIY Guide)

To calibrate your torque wrench, gather these supplies before you start: 

You are then ready to move on to these steps. 

  1. 1
    Record the measurement. Make sure your measurement is done from the center of the square drive, where the socket is attached. Do not use partial inches. Mark the handle where the measurement stops.  
  2. 2
    Secure the torque wrench. Lock the wrench into a vise. Leave plenty of room to attach the rope and weight to the wrench.  
  3. 3
    Complete the calculations. Multiply the distance you received from the first step by the weight you are using to get the appropriate inch-pounds.   
  4. 4
    Secure the weight. Tie a cable or rope around the weight with a loop at the other end to slide over the wrench handle. Don’t let it become too long that the weight will touch the ground.   
  5. 5
    Set the torque wrench to 25 ft-lbs. Hang the rope on the torque wrench so the weight is suspended. If the torque wrench clicks once, you need to set it to 26 ft-lbs. If it didn’t, it’s already calibrated.  
  6. 6
    If it clicks, you can adjust the torque wrench by tightening the tension spring. You will find it under the handle or near the middle of the wrench. Make the adjustments with the weight attached.  

Once your torque wrench has been calibrated, you can use it freely. If you are having trouble getting it properly calibrated, you might need professional support. Are you worried about how much to calibrate a torque wrench?

It might cost between $25 and $200, depending on what needs to be done, but that’s nothing compared to what it will cost if something isn’t torqued accurately.  

set of calibrated torque wrenches

How To Tell If A Torque Wrench Is Calibrated Correctly

You can take further steps to make sure the torque wrench is calibrated.  

  1. 1
    Make sure the setting is correct. There’s a big difference between 98 and 100. Don’t examine the scale on an angle. 
  2. 2
    Turn the wrench smoothly and steadily so you can hear when the click occurs. If you move too quickly, you might change the setting without knowing it. 
  3. 3
    Pay close attention to the conditions. If you are supposed to apply a specific torque to a dry fastener, don’t expect it to be correct in an unusually humid situation.  
  4. 4
    Do not push on the wrench body, but apply pressure to the handle. Force is measured at the pivot point below the head.  

Calibrating Popular Torque Wrench Brands 

Craftsman Torque Wrench 

Do you know how to calibrate a Craftsman torque wrench? If you have a beam torque wrench, you can use an eight-point socket between torque wrenches and check the clicker with the help of the beam. Make sure you check the measurements again in multiple ranges to ensure accuracy.  

Kobalt Torque Wrench 

Do you know how to calibrate a Kobalt torque wrench? You will follow the same steps we laid out above if you have a clicker-type torque wrench. However, if you need to have it professionally adjusted, expect to spend about $25 for the calibration and maybe another $50 for the certification.  

Pittsburgh Torque Wrench 

Do you know how to calibrate the Pittsburgh torque wrench? You could use a luggage scale, which makes the calibration a little bit easier. However, many of the Pittsburgh torque wrenches are fairly low-cost. Sometimes, it’s just best to purchase a new one rather than spend money having someone calibrate it.  

People Also Ask (FAQs)

Does AutoZone calibrate torque wrenches? 

AutoZone doesn’t offer torque wrench calibration. The best torque wrench calibration shops can be found in your local area or online, where you send your tools in for adjustments. If you don’t want to do it yourself, just make sure you read the reviews of the location you choose.  

How often do you need to calibrate a torque wrench? 

It depends on how often you use it and the conditions it is stored in. In normal conditions, you need to have it recalibrated every 12 months or 5,000 uses, whichever comes first.  

How much does it cost to calibrate a torque wrench? 

To recalibrate a torque wrench, you might spend as little as $25 for the adjustment and another $50 to have the results certified. In some cases, it makes more sense to purchase a new torque wrench.  

What are some tips to maintain a newly calibrated torque wrench? 

If you are careful with your torque wrench, it will maintain calibration. Always inspect the wrench for signs of wear and replace it when needed. Additionally, store the wrench unloaded to ensure accuracy.  


Now that you know how to test a torque wrench, it’s time to take charge of your tools. With a little care and regular calibration, you can ensure that every nut and bolt is properly tightened to factory specifications.