How to Measure a Moses Basket for a Fitted Sheet

Last Updated: November 5, 2026

Quick Summary

To measure a Moses basket for a fitted sheet, measure the mattress itself, not the basket, since the sheet wraps around the mattress. Take length, width, and depth at the widest points in inches, then repeat each measurement to double-check.

Measure the mattress out of the basket on a flat surface, since woven walls add an inch or more per side.
Record length, width, and depth to the nearest quarter inch, then measure a second time to compare.
For oval mattresses, measure length and width through the center, with width perpendicular to length.
For hourglass shapes, note both the widest and narrowest points so the elastic still holds.
If numbers fall between sizes, a soft jersey knit gives more stretch than woven cotton.

Why You Measure the Mattress, Not the Basket

The mattress is what your sheet has to fit, so the mattress is what you measure a Moses basket by. A handwoven Moses basket is never perfectly uniform.

Handmade baskets can vary in size, so measuring before you buy bedding is the smart move. That single habit prevents the most common problem: a sheet that looks right in the package but pulls loose or bunches up on the mattress.

Here is the good news. Measuring takes about five minutes, and you only need a soft tape and a way to write the numbers down.

What You'll Need Before You Start

Gather four simple things and you're ready. A flexible soft measuring tape works best because it follows curves. A pencil and paper, or your phone's notes app, keeps the numbers handy when you shop.

A soft measuring tape, not a stiff metal ruler
Paper and pencil, or a notes app
The mattress itself, out of the basket
A flat surface such as a table or floor

One more thing helps: a helper. An extra pair of hands keeps the tape straight while you read the number. If you're measuring solo, tape one end of the tape down so it doesn't slip.

Step by Step: How to Measure a Bassinet Mattress

Measuring a bassinet mattress comes down to three numbers: length, width, and depth. Take each one at the mattress's widest point, write it down in inches, and repeat once to double-check. That's the whole method. The detail that separates a good measurement from a bad one is where the tape sits and how you hold it, so here is the full procedure.

Setting Up the Mattress

Take the mattress out of the basket and lay it flat on a table or the floor. A flat surface matters because a mattress propped against a wall or still curved inside the basket will read short.

If you are measuring solo, tape one end of the soft tape to the table so it stays anchored while you walk the other end. A helper is easier, but tape works fine.

Measuring Length and Width

Length is the longest end-to-end distance.

Width is the same idea across the mattress. Find the widest point, which for most Moses basket mattresses is the middle, and run the tape from edge to edge perpendicular to the length.

Write both numbers down immediately, in inches, to the nearest quarter inch. Rounding to the nearest inch is where most ordering errors start.

Measuring Depth and Thickness

Depth is how thick the mattress is, from the flat top surface to the bottom. Pinch the tape against the side wall of the mattress, keep it vertical, and read where the bottom edge sits. Do this at two or three points around the mattress, because a hand-finished mattress can be slightly thicker in the middle than at the edges. Record the largest number.

Depth matters because a thicker mattress needs a sheet with deeper corners, or the elastic will pop off during the night. Record depth last so all three numbers sit together on your page.

Recording and Double-Checking

Write your three numbers in a single line, for example: length 28 1/2 in, width 15 3/4 in, depth 1 1/2 in. Then measure each one a second time without looking at your first numbers, and compare. If the two readings differ by more than about a quarter inch, the tape slipped or the mattress shifted, so measure again.

Watch out: measuring the basket rim instead of the mattress is the single most common error. The woven walls add an inch or more on every side, so a sheet chosen from the basket's outer dimensions will be too big and will bunch under your baby.

With those three numbers written down and confirmed, you have everything you need to compare sheet listings, including ones that list depth separately from length and width.

Browse the full range of Moses basket sheets once you have your numbers in hand, and you can compare sizes side by side.

A Fitted Sheet for an Irregular-Shaped Moses Basket

The waterproof fitted sheet keeps the mattress clean and dry. Pair it with a soft sheet on top and the whole setup stays put through the night.

A fitted sheet that stays snug is one less thing to think about at 3 a.m. Measure once, write it down, and you'll shop with confidence every time.

Measuring your mattress is a small step that makes a big difference in how safe and snug your baby's sleep space feels. Plum+Sparrow handweaves each Moses basket with care, includes a custom fit mattress, and offers sheets made to match, so you can set up a cozy first bed without the guesswork. Explore the handwoven baskets, breathable cotton sheets, and waterproof covers, and get started with Plum+Sparrow to build a sleep space your little one can rest in and your family can pass down.

Jersey Knit Fitted Sheet