Introduction: Shorten a Cardboard Box.

 Many times when packing an item to ship I find I still have alot of space left in the box.  More space means more packing material is needed and the box ends up weighing more.  Extra space also means more chance of the the item moving around during shipment and possibly getting damaged in the process. This guide will show you how to shorten the height of a cardboard box.   I used a smaller box since its easier to take pictures, but this technique will work with boxes of all sizes.   

Tools needed:

Cardboard box that is too high
Pair of Scissors
Long ruler or straight edge
Pen or marker

Step 1: Decide How Much to Shorten the Box

Flatten the cardboard board you are going to shorten and decide how many inches to take off.  I decied to take 3 inches off this box.  The box's bottom actually the top of the bottom flap, so remember to lift the flap up and measure from there.   Using the pen or marker, mark the box at 2 different spots 3 inches from the bottom using the folded up bottom flap as your guide.

Step 2: Create a Crease on the Box

Line up the ruler along the 2 measurement marks we made earlier.  Hold the ruler down firmly with one hand so it doesn't move.  A  closed pair of scissors to create a crease along the side of the ruler that is lined up on the measurement marks.  Press down firmly with enough pressure to create a crease, but not enough to tear the box.

Step 3: Cut the Box Edges

Cut the box at the middle up to the crease (this part is one of the outer edges of the box when it's folded.)  Cut the right edge up to the crease and do the same for the left side.

Step 4: Fold Up the Box and Create Another Crease.

Fold up the the newly created flaps.  This will expose the inside of the box.  Using the folded up flaps as a guide, create another crease on the inside of the box with the closed scissors.

Step 5: Cut the Middle of the Box

Cut the middle of the box up to the folded up flaps.

Step 6: Fold Over Bottom Flaps

Fold over the bottom flaps.  You may need to cut them if they extend past the edge of the box, but in most cases its fine to leave them uncut.  Make sure to tape the box securely to prevent it from popping open.

Step 7: Finished

Here you can see how the much we shortened the box.  Once you get more experience with cutting and folding boxes, it should only take less than a minute to do.  You'll soon be saving a ton of money by reusing boxes you previously thought were too big.