Discover the three main types of calipers, the four key measurements they make, top brands, limitations, parts of a caliper and more.
Forget the tape measure or ruler.
FYI, measuring calipers are not to be confused with brake calipers. Those are different and not discussed here.
There are 3 main types of calipers in use today. All 3 can take the 4 main caliper measurements (listed first).
Let’s dive into your measuring caliper options.
What is a caliper?
A caliper is a measuring device. In fact, it’s a precise measuring device that can measure diameter, thickness, depth and take compound measurements. There are three main types which are set out below.
Parts of a caliper
Below is a diagram setting out the different parts of a caliper.
What are the four main caliper measurements?
1. Outside diameter measurement
It measures the outside diameter of something. Check out the following photo.
2. Inside measurements
Another common caliper measurement is an inside measurement such as the diameter of a hole. Check out the following example:
3. Depth measurements
Depth-measuring calipers measure with precision, the depth of something. A good example is tire tread. Check it out:
4. Step measurements
Step measurements, aka compound measurements, requires two or more measurements to figure out the answer. It may include both an outside and inside measurement or any combination of outside, inside and depth.
3 Main Types of Calipers (plus 3 others)
There are three main types of calipers. They all can take the 4 required measurements. It’s the read-out that differs. Here they are.
1. Digital caliper
This is the newest type of caliper to hit the scene and these are awesome due to precision. You don’t have to stain your eyes to obtain a reading.
Here’s an example:
Digital calipers can take a variety of measurements such outside diameter, inside, depth and step measurements making them very useful.
Let’s talk about these measurements because they are different. In fact, some other types of calipers are designed for just one of those measurements. Digital is great because it’s like a 4-in-1 caliper.
How precise are digital calipers? They are accurate to approximately .2mm or .01 inch.
If you’re willing to spend more (north of $100), you can get precision down to an incredible .05mm. To put that into perspective, regular thickness human hair is .06mm.
2. Vernier Caliper
Vernier calipers are much like digital except you don’t get a digital read-out or screen. It’s an old-school “ruler-style” caliper.
While good, it’s hard to get as precise of a reading because you’re looking at the measurement on a ruler style report. Is it a touch bigger than a millimeter? If so, how much. Digital will report precisely.
Another downside is some analog calipers may not offer metric system. Digital usually offers both digital and imperial.
The plus side is you don’t get the headaches you do with anything digital such as batteries dying or any technical hiccups that result in bad readings. Analog is a work horse and I’m sure there are folks out there who have had the same old analog caliper for decades.
4. Dial Caliper
A dial caliper is as the name suggests, which is you read your measurements from a dial.
Other caliper option
Spring Joint Caliper
Spring joint calipers operate similarly to the above-listed calipers except without a measurement read-out option, you lock in your measurement then put it against a ruler.
What are the main caliper brands?
Mitutoyo are excellent calipers are by far the most popular. You can spend hundreds or even thousands. When you need optimal precision, Mitutoyo is the way to go. If you research your caliper purchase and are looking for a higher quality caliper, you’ll likely notice just how popular and prominent Mitutoyo Calipers are. They sell calipers ranging from just under $100 to over $3,000.
Starrett manufactures and sells ridiculously accurate calipers up to .02 mm accuracy. When you need this level of accuracy, be prepared to spend some serious money – over $2,000.
VINCA sells lower-end calipers where you don’t need a high-level of precision.
The most obvious limitation of measuring calipers is the size of object they can measure. As you can see from the many examples and types above, they are only so big and you can only measure something that the caliper itself accommodates.
Other limitations include precision. While most calipers are very precise, you may require a measurement more precise than what the caliper can offer. This means you may need to seek out a higher quality, more expensive caliper for the job.