T shirt upcycle to open back tank top

Turning old t shirts into great tank tops for the gym is probably my favorite type of quick and easy upcycle. There are so many things you can do with a t shirt! And you can recreate almost any gym shirt style you want out of a t shirt (and for a whole lot cheaper than buying said gym shirt).

Lately I’ve been seeing a lot of these open back tank tops with a cross-over detail at the neckline. It looked like a fun style to try out, so I grabbed an old worn out t shirt from my dresser and gave it a try! And I love how it turned out! The best part is that you can wear it two ways, either with the back open and flowy or you can tie the bottom corners together for a cool look that shows a bit less skin.

I used this worn out loose fitting t shirt for this project. It had a hole in one of the armpits (why do the armpits of my shirts always wear out first??) so it needed to be transformed into a tank top.

Ok, let’s get into how I made this open back tank top!

*This list contains affiliate links for some of the materials I used in this DIY, so if you purchase through one of my links I receive a small commission at no extra cost to you. This really helps to support my site so I can continue to create DIY and sewing tutorials for you!

What you need:

• loose fitting t shirt
• sewing machine
• ballpoint or jersey needle
• double needle (optional)
• thread
• scissors
• seam ripper
• chalk or fabric marker
• ruler to draw a straight line
• pins
• iron

Steps:

1. Seam rip the collar off the shirt
2. Cut a line straight up the center of the back of the shirt
3. Hem the center back edges
4. Create the overlap at the back neckline and stitch in place
5. Reattach the collar
6. If you want a tank top: cut your armhole shape and hem the armholes

Instructions:

Step 1

My first step is to seam rip off the collar of the shirt. My shirt had a binding on the back neckline and the shoulder seams, so I seam ripped the binding off the back neck. Then I trimmed it close to the beginning of the shoulder seams and tacked it down so that it would stay on the shoulder seams. If your t shirt doesn’t have this binding, you can just skip this and go straight to removing the collar.

After I had that binding off the neckline, I seam ripped off the collar. This took a while because there were a lot of threads holding on the collar!

Step 2

Next, I laid the shirt as flat as possible with the back facing up and drew a straight line up the center of the back of the shirt. You can find the approximate center by folding the shirt in half or measuring from each side and marking the center.

Then I just cut along this line with my scissors.

Step 3

At this point I ironed the shirt because I just can’t stand sewing wrinkly fabric, but this is obviously up to you! I then hemmed the two center back edges that I had just cut open. I used my double needle for this, but a zigzag or stretch stitch would work just as well.

Step 4

Next, I created my overlap at the neckline. You can decide which side you want to overlap and how far to overlap the edges. Just keep in mind that your head needs to fit through the opening and if you overlap it a lot you might need to make the collar smaller before reattaching. I just did a slight overlap of a little over an inch. Once you’ve decided how to overlap it, pin it in place and sew the edges together with a zigzag along the edge.

Step 5

Now it’s time to reattach the collar! To do this turn the shirt inside out and pin the collar to the right side of the neckline. I used four equally spaced pins to make sure the fabric of the shirt would be equally stretched around the neckline to fit the collar.

Next, sew the collar to the shirt, stretching the neckline between the pins to fit the collar. I used my serger to sew on the collar, but a zigzag stitch on a regular sewing machine would work as well.

Then turn the shirt right sides out and iron up the collar.

Step 6

Next, I needed to turn the shirt into a tank top because of the armpit hole I mentioned before. If you want to leave the sleeves on your shirt, feel free, and you’re done! I tried the shirt on and drew out the armhole shape I wanted on one side.

I cut along this line to remove the sleeve.

To mark out an identical armhole on the other side, I first folded the shirt with the front to the inside and traced the front armhole.

I then folded the shirt the other way (with the back to the inside) and traced the back armhole. This is a bit more challenging than the front because you have to carefully push the front armhole back out of the way so you can trace just the back. I originally accidentally traced the front armhole curve (the line you see in the first photo below) but corrected it to the line I’m pointing at in the second photo.

Next, I cut along my lines to remove the other sleeve, then hemmed both armholes with my double needle. As with everything else, if you don’t have a double needle a regular zigzag works fine.

Just give everything a good ironing to flatten all your stitching and you’re done!

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Here’s some of my other t shirt upcycles you might be interested in:

• No sew t shirt upcycle to front tie crop top
• Easy DIY racerback tank top upcycle from t shirt
• DIY strappy tank top upcycled from t shirt
• T shirt upcycle to crop top with lace up detail