Plain and simple.....
Shortening metal (aka jeans) zippers doesn't have to be a traumatic experience if you know a few tips.
There is nothing worse than your zipper pull coming off the top so the rule-of-thumb is to shorten a heavy-duty jeans zipper from the bottom. Very simple 'they' say.....just cut off the bottom stop and stitch a thick bartack along the bottom - fool proof right? Well, I had an 'incident' occur a while back where the zipper pull went right over my thick hand-stitched bartack.
I learned a new trick from Kenneth D, King when he was at Janie's Sewing Corner for a workshop. He also demonstrates the technique on his 'Jeanius' class on Craftsy. No more shortening zippers from the bottom and no more thread tacks for me.
For this technique, the zipper will be shortened from the top.
For this technique, the zipper will be shortened from the top.
To start, take a look at your metal zipper to determine if there are one or two top zipper stops.
The red and blue zippers have only one top zipper stop on the left.
This black zipper has two top zipper stop, one on each side.
If uncertain what length is required lay your zipper on top of the fly to determine the length of the zipper required. Even if the exact length is known, it is good practice to double check by placing the zipper on the garment. The bottom zipper stop is generally placed 3/4-1-inch above the bottom of the zipper fly.
This example is for a pair of jeans. The view is from the inside. A full yoke pocket is shown in the view and the zipper is aligned on top of the left fly shield. With a pin, mark the placement where the top of the zipper must stop. This will generally be just below the waistband seam allowance. In the example (below) the seam allowance is 3/8-inch. I want the top zipper stop to fall just below this point.
UNZIP THE ZIPPER! This is a critical step that is easy to forget. It is easy to get excited and cut off the excess zipper length only to realize that the zipper pull has been cut off too. I like to place a safety pin through the zipper tape as a bit of insurance so I don't accidentally close the zipper and remove the zipper pull.
Very carefully, remove the top zipper stop(s) using a pair of diagonal wire cutters. But DON'T LOSE THE ZIPPER STOP!!
Have no fear though. If you there is worry about losing or inability to remove zipper stops, these can be ordered. I highly recommend ZipperStop for ordering extra top and bottom (if needed) zipper stops, as well as, specialty sizes and styles. A standard jeans zipper is a size #3. They come in brass, gold, or silver.
Most likely, the zipper tape is much longer than needed. All of the individual teeth above the pin mark will need to be removed. I shorten some of the excess off the zipper tape so I have less to remove.
I know I will need at least 3/8-inch of the cloth zipper tape above the top stop to properly attach the zipper to my jeans. I will measure and cut off excess above that point.
(If you haven't removed the top zipper stop, don't lose those pieces -the top zipper stop is still attached to them.)
Using the same diagonal pliers, carefully pull off the individual zipper teeth. Hold the tape firmly with one hand and with the other hand pull the zipper tooth off sideways (perpendicular to the tape). The cloth tape may fray a bit. Don't worry about it and DON'T cut the cloth tape. You need all that excess cloth tape to be stitched into the waistband seam allowance.
Once all of the extra teeth have been removed, place a top zipper stop at the end of the teeth as close to the teeth as it will allow and press firmly with a pair of pliers.
I originally tried to use a pair of needle nose pliers but then I found these crimping pliers easier to work with.
I highly recommend that if you have a zipper with two top stops (one on each side), use both.
The first time I tried this was a failure. I had a YKK zipper that only had one top zipper stop. What I failed to realize that the zipper side without the stop must be even with or one zipper tooth longer than the side with the zipper stop. Looking back at this image, see the side with the arrow? The top tooth is even with the zipper stop.
The red and blue zippers have only one top zipper stop on the left.
This black zipper has two top zipper stop, one on each side.
If uncertain what length is required lay your zipper on top of the fly to determine the length of the zipper required. Even if the exact length is known, it is good practice to double check by placing the zipper on the garment. The bottom zipper stop is generally placed 3/4-1-inch above the bottom of the zipper fly.
This example is for a pair of jeans. The view is from the inside. A full yoke pocket is shown in the view and the zipper is aligned on top of the left fly shield. With a pin, mark the placement where the top of the zipper must stop. This will generally be just below the waistband seam allowance. In the example (below) the seam allowance is 3/8-inch. I want the top zipper stop to fall just below this point.
UNZIP THE ZIPPER! This is a critical step that is easy to forget. It is easy to get excited and cut off the excess zipper length only to realize that the zipper pull has been cut off too. I like to place a safety pin through the zipper tape as a bit of insurance so I don't accidentally close the zipper and remove the zipper pull.
Very carefully, remove the top zipper stop(s) using a pair of diagonal wire cutters. But DON'T LOSE THE ZIPPER STOP!!
Have no fear though. If you there is worry about losing or inability to remove zipper stops, these can be ordered. I highly recommend ZipperStop for ordering extra top and bottom (if needed) zipper stops, as well as, specialty sizes and styles. A standard jeans zipper is a size #3. They come in brass, gold, or silver.

Most likely, the zipper tape is much longer than needed. All of the individual teeth above the pin mark will need to be removed. I shorten some of the excess off the zipper tape so I have less to remove.
I know I will need at least 3/8-inch of the cloth zipper tape above the top stop to properly attach the zipper to my jeans. I will measure and cut off excess above that point.
(If you haven't removed the top zipper stop, don't lose those pieces -the top zipper stop is still attached to them.)
Using the same diagonal pliers, carefully pull off the individual zipper teeth. Hold the tape firmly with one hand and with the other hand pull the zipper tooth off sideways (perpendicular to the tape). The cloth tape may fray a bit. Don't worry about it and DON'T cut the cloth tape. You need all that excess cloth tape to be stitched into the waistband seam allowance.
I originally tried to use a pair of needle nose pliers but then I found these crimping pliers easier to work with.
I highly recommend that if you have a zipper with two top stops (one on each side), use both.
The first time I tried this was a failure. I had a YKK zipper that only had one top zipper stop. What I failed to realize that the zipper side without the stop must be even with or one zipper tooth longer than the side with the zipper stop. Looking back at this image, see the side with the arrow? The top tooth is even with the zipper stop.
Do NOT do this. The zipper pull will come off and get stuck.
Zip it Good!