A masu box is one of those origami projects that looks fancy but folds up fast. One square of paper, a handful of creases, and you have an open paper box for trinkets, sweets or paper clips on your desk.
This version follows the easiest method from Paper Kawaii, who has folded hundreds of them. A small change right at the start means fewer creases and cleaner walls, so the finished box looks neat instead of crumpled.
Work on a flat surface and press every crease hard. Sharp folds are the only thing holding this box together - there is no glue or tape doing the job.
Working out the finished size
A masu box finishes at roughly half the width of the square you start with. A 15 cm sheet gives a box about 7.5 cm across and a little over 2 cm deep, which suits a ring or a handful of sweets. Scale the square up and the box grows in proportion, so a 30 cm sheet lands near 15 cm across.
Paper weight matters more than it sounds. Standard origami paper works, but the walls stay firmer if you use something slightly heavier - patterned scrapbook paper around 120 gsm is about the ceiling before the corner tucks get too bulky to sit flat.
Adding a lid
The lid is the same fold again with one change. Start from a square about 5 mm larger on each side than the one you used for the base, or fold the same size and leave a slightly wider gap when you bring the edges to the centre. Either way the second box slips straight over the first.
Contrasting paper for the lid is the easy win here - a patterned lid over a plain base looks deliberate, and it costs nothing extra.
What a paper box is good for
Small gift packaging is the obvious one, especially for jewellery where a bought box costs more than the wrapping. They also work as desk drawer dividers, seed sorters when you are collecting from the garden, and disposable paint pots. Fold a few from newspaper and they become bin liners for peelings that go straight in the compost.
The easy origami box, step by step
Seven steps, one square, about five minutes once you have folded a couple. The order matters: crease both diagonals, bring all four corners to the centre for the blintz base, fold the top and bottom edges in, then unfold everything except the two side corners. Those two stay folded and become the short walls. Everything after that is reading creases you already made.
If a step diagram looks nothing like your paper, count your creases rather than your folds. The blintz base should show a square outline with four diagonal lines inside it. No square outline means the corners did not meet cleanly at the centre, and the walls will lean.
When the walls will not stand up
Loose walls come from one of two things. Either the corner tucks are not pushed all the way down into the base, or the paper is too light to hold its own shape. Press the tucks flat with a bone folder or the back of a spoon, then run your thumb along the inside of each corner from the floor of the box outward.
Paper under about 80 gsm makes a box that slumps as soon as you put anything in it. Patterned scrapbook paper around 120 gsm is the sweet spot. Above that the corner tucks get too thick to sit flat and the base rocks.
Paper boxes for gifts and Christmas
A masu box with a lid is a jewellery box that costs the price of two sheets of paper. Earrings, a ring, a pair of cufflinks: box them, tie a length of baker's twine round the lid, and you have wrapped the present at the same time. Patterned lid, plain base, or the other way round.
They also work as Advent boxes. Fold twenty four in two contrasting papers, number the lids, fill each with a sweet, and line them along a shelf. And a shallow one folded from a 30 cm sheet holds a gift card flat so it does not rattle around inside something far too big for it.
