How to Alter a Tank Top Easily (Resize, Crop, Twist, Tips)

Resizing a tank top isn't a complicated business. Before starting, work out exactly what you like about the top (perhaps the length is hitting just the right spot. Maybe there are some graphics that you don’t want to lose) and exactly what you don’t (maybe the neckline is too low, or the armholes are gaping).

Once you’ve decided what needs to change and what doesn’t, it’s then simply a case of working out what alterations are going to be needed and getting started.

How do You Resize a Tank Top?

Most alterations don’t require any advanced sewing skills, and some can even be done without sewing at all.

Up next, we’ll look at a few of the most common reasons for re-sizing a tank top… and how to do them.

How to Alter a Tank Top That's Too Big

If your tank top is too big, a professional tailor should have it fitting like a glove in no time. But why pay someone else when you could do it yourself at home, cheaply, easily, and quickly?

Providing you know which way of a needle is up, re-sizing a tank top is one of the easiest sewing challenges you can set yourself. Here’s how to do it.

The Method

  • Step 1 - Try the tank top on, wrong side out. Adjust the shoulder straps until you find a length you’re happy with. Pin in place.
  • Step 2 - Pinch the fabric underneath one of the arms, tighten to the desired fit, then pin along the armhole seam. Repeat on the other side.
  • ​Step 3 - Tighten the fabric 2 inches down from where you placed the first underarm pin. Pin. Repeat on the other side. Tighten and pin your way down the rest of the top, alternating between the left and right sides as you go.
  • Step 4 - If you want to adjust the length as well as the width, fold the hem up to the desired length and pin in place.
  • ​Step 5 - Take the tank top off, taking care not to prick yourself on the pins.
  • ​Step 6 - Lay the tank top inside out on a flat surface. Measure both sides of the top to make sure the adjustments you’ve made are even. Adjust the pins if required.
  • ​Step 7 - Start sewing the tank top at the shoulder straps, using a stretch stitch or a zigzag stitch. Continue sewing down the lengths of the top, using the pins as your guide. Sew the hem with a ¼ inch seam allowance.
  • Step 8 - Try the top on to check for fit. Make any adjustments necessary. Once you’re happy with the new size, cut away any excess fabric. Finish by sewing a stretch overlock stitch over the seam allowances.

Making a Tank Top Bigger


Making a tank top smaller is one thing, but is making one bigger just as easy? Or even possible at all? Yes and yes… although you might need to get a little creative about how you do it.

Of course, if the top has plenty of excess fabric tied up in the seam allowances, you could simply let it out. If, on the other hand, you want to mix things up a little, you could try one of these methods instead.

Add Slits - If the thought of sewing makes you break out in a sweat, there’s an easy solution – slits. This method will preserve the garment as it is – perfect if it’s made from a super-comfortable material or has any graphics you don’t want to mess with. Where you place the slits is up to you. You could try cutting them into the sides for a loose, flowy style, or down the front from the neckline to give a more comfortable fit around the bust.

Add a Panel - If your tank top's both too small and too boring, give it a bright new look with some panels. Simply make the necessary slits (you can either do one long, vertical slit at the back or add two slits at the side) before inserting triangular-shaped pieces of fabric into the slits.

How to Alter Tank Top Straps

Some people might think of tank tops as leisurewear, but the right style can work as well in the office as on the beach. But there’s a problem… the neckline. What’s fine on the weekend can be widely inappropriate during the week. Worse still, the difference between the two can be as little as one or two inches.

If your tank is just a little too low to wear to the office, don’t despair. A few alterations to the straps can make a big difference to the overall look, and instantly make any camisole or beater worthy of work.

The Method

  • Step 1 - Flip the tank inside out and put it on.
  • Step 2 - Adjust the straps until you find a comfortable fit. Pin in place, ensuring the seam runs along the middle.
  • Step 3 - Remove the tank. With a fabric pen, mark both sides of the seam along where the pins are.
  • Step 4 - Remove the pins and line up the lines on both the shoulders. Use a stretch stitch or a zigzag stitch to stitch along the lines.
  • Step 5 - Trim any excess fabric from the seam allowance, open the seam and pin the edges so it lies flat. Repeat on the other side.
  • Step 6 - To finish, stitch a stretch overlock stitch over the seam allowances.

How to Twist Tank Top Straps

Bored with the style of your tank top? Then give it a brand-new look with some twisted straps. It’s cute, it’s fresh, and it can be done in minutes.

The Method

  • Step 1 - Cut along the existing seam on both straps. Twist the front straps, moving in the opposite direction to the neckline.
  • Step 2 - Check that both sides look even, pin to hold, then re-stitch the shoulder seam in place using a 1/4″ topstitch. If you prefer, you can use fabric glue instead of stitching.

How to Alter a Racerback Tank Top


Racerback tank tops are versatile, comfortable, and incredibly easy to wear. But if you’ve lost some weight or accidentally bought a tank that’s just a little roomier than you’d like, they can easily look shapeless and ill-fitting.

If your tank isn’t meeting your style standards, a few modifications should soon do the trick. If you prefer, you can follow the usual method of trying the tank on, pinning to the new size, and then either sewing or serging a new seam.

If you want to try something a little different (and providing you have another racerback tank that fit’s like a dream), you could try this easy alternative instead.

The Method

  • Step 1 - Place a well-fitting tank on a flat surface with the seam pressed flat. Lay the tank to be altered over the top, with the shoulders aligned. Both tanks should be facing wrong side out.
  • Step 2 - Trace the outline of the smaller tank around the larger one to indicate which areas need to be removed. You can either use tailor's chalk or a washable fabric pen.
  • Step 3 - Serge a new seam using the lines as your guide. If you don’t have a serger, use your sewing machine to stitch a new seam. If you sew rather than serge, remember to trim any excess fabric and finish the new seam allowance by opening the seam, pinning the edges flat, and using a stretch overlock stitch over the seam allowances.

How do I Turn an Oversized Shirt Into a Tank Top?

No matter how big your t-shirt drawer, the chances are you get a little bored with its contents from time to time. But rather go to the effort and expense of buying yet another t-shirt to add to the collection, why not customize one you already have instead? With a few tweaks, a plain t-shirt can be turned into a cute little tank. Check out how with the easy to follow tutorial.

The Method

  • Step 1 - Before you start getting snip-happy with the scissors, mark out the areas of the t-shirt that need to be trimmed. You’ll need to draw cutting lines at the sleeves and the collar for sure, but you might also want to consider adding slanted lines from the bottom hem up to the center front of the shirt (creating an upside-down triangle effect) if you want a tie front top.
  • Step 2 - Press the t-shirt well with an iron. A wrinkle-free, smooth fabric is far easier to cut in sharp, precise lines than one with multiple folds.
  • Step 3 - Use fabric scissors to cut along the lines. Once you’ve finished cutting, give the shirt a light tug to help the raw edges roll-up on themselves (if you prefer clean lines, you can always stitch new hems in place instead. If you’re happy to keep things casual, this method for creating a “rolled hem” is the easiest). And that’s it – a brand new tank in just a few minutes.

How to Make Tank Top Armholes Smaller


Slouchy may be fashionable, but there’s a fine line between slouchy and ill-fitting – and that line usually comes into play when you’re dealing with an oversized armhole. If the armholes of your tank are revealing a little more than you’d like, you can easily rescue them (and your modesty) with a few little tweaks.

When it comes to making tank top armholes smaller, you’ve got one of three options:

Option 1: Add a Dart - If the armholes of your tank top are gaping, adding a dart should soon bring them into line. Simply flip the tank inside out and pinch the amount of fabric that needs to be taken in. Sew the fold into a dart using a narrow zigzag. Bear in mind that the dart will change the style lines to some degree – if you can put up with that, you’ll find it the easiest, quickest solution.

Option 2: Add a Band - If you don’t want to add a dart to your tank, you might want to consider adding some extra fabric into it with either a band or binding.

Start by pinching the fabric in the same way you would if you were making a dart. Use a fabric pen to mark the armhole around 1-inch past the fold. Cut out your binding or band so that’s it’s that much smaller than the existing armhole (e.g. if you pinch a 1-inch dart, the band should be around 2 inches smaller than the armhole). Sew the band or binding in place, being sure to ease it out as much as possible in the area that’s gaping.

Option 3: Add an Elastic Edge - Elastic is an easy way to bring a gaping armhole to heel. Simply mark out your dart in the same way as the previous option, cut the elastic to a couple of inches smaller than the armhole (depending on how much you want to ‘shrink’ it by) and sew in place, making sure to stretch it out as much as possible around the area that’s gaping the most. Job done!

How to Crop a Tank Top


Cropping a tank top can give it a whole new lease of life. It’s also one of the easiest and simplest ways of upcycling your wardrobe – simply measure how much you want to remove, draw a line to make the new hemline, press the top, then get cutting. You don’t even have to sew the new hem in place if you don’t want to – simply give the fabric a little stretch, and it’ll create a rolled hem all by itself.

That’s the basic version, but sometimes, you might want to get a little more creative. To turn your tank into a cute, designer inspired crisscross style crop, try this easy tutorial.

The Method

  • Step 1 - Try the top on. At the back of the tank, measure a line a few inches below where your bra strap ends. Unless you’re super flexible, you might want to have a helper mark out the line for you.
  • Step 2 - Remove the tank top and cut out the back, using the marked line and the line of the seams (which can be left on) as your guide.
  • Step 3 - Make a mark in the middle of the front of the tank top. Cut all the way down the front of the tank top, from the neckline to the hem. You should be left with a completely open front.
  • Step 4 - Now you’ve created the shell of your crop top, you can have fun finding different ways of tying it. Remember that once you’re done wrapping, tuck the top edges under for a smooth line.

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