How to Measure a Zipper
There are two important measurements on every zipper – length (noted in inches or centimeters) and gauge, which is typically accompanied by a # next to it.
Both are equally important when it comes to determining the right zipper replacement.
This guide will show you how to measure both.
What is Zipper Gauge (aka Zipper Size)?
Also known as zipper size, the gauge of a zipper refers to the width of its teeth, in millimeters, when it’s zipped shut. Whenever you see a number and hash symbol (e.g., #2) next to a zipper, this is referring to the zipper’s gauge.
The larger the number, the heavier the gauge, and, therefore, the heavier the zipper.
How to Measure Zipper Gauge
Measuring zipper gauge is easy. Measure the zipper teeth, in mm, horizontally when the zipper is closed. Make sure you don’t include any tape in your measurement – it’s just the teeth you want to measure.
You can use a measuring tape, ruler, or digital caliper. If your measuring tool only includes cm and inches, convert them to mm to figure out the gauge (1cm = 10 mm; 0.25” = 6.35mm).
Some guides suggest looking at the back of the zipper's slider to determine the zipper gauge, but this isn’t the best solution. The letters and numbers on the back can mean a whole host of things, depending on the manufacturer.
The best - and most reliable - way to determine a zipper's gauge is to measure the zipper yourself.
How to Measure Zipper Gauge if the Zipper Won't Close
If you’re working with a broken zipper that no longer
closes, you can work out its gauge by measuring one side and doubling it. You might have to round up or down slightly (to account for any overlap that occurs when the teeth are closed), but it should be fairly clear what the gauge is based on the measurement of a single side.
How to Measure Zipper Length
Generally, measuring the length of a zipper is easier than measuring the gauge of a zipper.
Zipper length is often measured in inches. The guidelines for measuring a zipper's length differ slightly based on type of zipper.
Regardless, you never include any zipper tape where there’s no chain in your measurement. To put it another way, zippers will always have some extra tape at the top and sometimes on the bottom, which is usually for cutting and sewing depending on the project. You don’t include this in your length measurement, as it’s essentially “waste” material in this regard.
Measuring Closed-End Zipper Length
Closed-end zippers are pretty easy to measure because they have obvious ends.
Measure the length from the top of the top stop to the bottom of the bottom stop to get the required length.
Measuring One-Way Separating Zipper Length
Also known as open-end zippers, these are just as simple to measure.
Go from the top of the top stop to the bottom of the retainer box, which is the part that keeps the zipper on its chain.
Measuring Two-Way Separating Zipper Length
Two-way separating zippers don’t have retainer boxes at the
bottom, as the second slider covers this purpose.
As such, you’ll want to measure from the top of the top stop to the bottom of the reinforcement tape.
Measuring Head-to-Head (Two-Way Bag-Style) Closed-End Zipper Length
Two-way bag-style zippers are closed-ended, and similar to one-way closed-end zippers, they are measured from end to end from each stop.
Unlike one-way closed-end zippers, however, these zippers have a bottom stop at each end, as opposed to a bottom stop at one end and top stops at another.
Measure from the top of one bottom stop to the bottom of the other bottom stop.
Ready to Shop?
Now that you know how to properly measure zipper gauge/size and zipper length, you can shop for what you need.
Our helpful shop filters will allow you to segment your searches by gauge and length.
As Seen In:
Let customers speak for us
The zipper I received is exactly what I needed to fix my husband’s coat. Thank you!
good quality zippers. Always able to find what I need.
Haven't put them on the zip yet but if they work like the rest of the company I think they will be perfect. Service from you guys was exceptional give we are in New Zealand, they were here in no time. Communication was excellent and we can't thank or rate your company highly enough. Cheers, Gary.
The polished gold zipper replaced a low quality one on a black dress. The zipper is on the dress front and is dramatic and eye-catching. It’s a million times more secure and beautiful than the zipper it replaced. The new zipper came quickly and is perfect.
Purchased four 18" zippers for sofa pillows. These zippers open and close so easily. So happy I purchased these.
This was my first order from Zipper Shipper — I ordered a #3 zipper for a pillow project. It arrived in perfect shape. I couldn’t find the delivery (it was in the mailbox — didn’t think to look there — so I sent a note it had not arrived. I received a response THE SAME DAY!! Very impressed with the customer service. I will buy all of my zippers from Zipper Shipper from now on.
Love that these are made in the USA. Zippers came in a small plastic bag along with continuous coil zipper. Super excited to use these.
Quality zippers and fast shipping.
I'm so glad I found Zipper Shipper! The prices are great, shipping was FAST and the quality is perfect - definitely my #1 place to source my zippers. I will be back to order more soon!
It was delivered in a timely fashion, and it was what I expected.
Great zippers that I've always been happy with. They always seem to have what I need in stock, or quickly available.
First time ordering and will absolutely be placing more orders. Zippers are perfect, shipping was fast, and the price point is great!
This is a very reliable company. I have placed several orders with them and have never been disappointed. I make pillow covers with a zipper closure. The colors are true. I have ordered zippers from other companies and the colors were several shades off. The shipping is fast too.
Zipper is the perfect length, size, and color for my needs-replacing zippers in leather chaps. Fast shipping and easy ordering. Thanks Zipper Shipper.
