How to measure the throat space on your machine

Two measurements. Width: from the right-hand side of the needle to the body of the machine, along the bed. Height: from the bed surface straight up to the lowest point of the arm above it. Take both with the presser foot up and the needle at its highest position, and write both down - the second one is the one that matters.

Why measure it yourself at all

Because for a large share of machines, nobody published the number. Across the machines on the throat space chart, several makers publish a single width with no height beside it - bernette gives 9 in for the 79 and no height, Brother gives 7.4 in from needle to arm for the SE2000 and no height. If your machine is older or was sold under a store brand, there may be no specification page left at all.

And because the decision you are trying to make is a comparison. “Is it worth upgrading?” is unanswerable until you know what you are upgrading from.

What you need

• A tape measure or a rigid ruler. A flexible dressmaker’s tape works for width but sags on the height measurement - a ruler is better for that one.
• Two minutes.
• Somewhere to write down two numbers.

Measuring the width

Set the needle at its highest position and raise the presser foot. Lay the tape flat on the bed of the machine, starting at the right-hand edge of the needle, and run it horizontally to where the vertical body of the machine rises out of the bed.

Read the number where the tape meets the body. That is your width - what the industry calls the throat, the harp or the needle-to-arm space, all of which mean the same thing and are covered on harp space vs throat space.

Measure from the needle, not from the edge of the needle plate. The needle is the fixed reference every manufacturer uses, and starting from the plate edge will flatter your machine by an inch or more.

Measuring the height, which is the one people skip

Stand a ruler on the bed of the machine, just to the right of the needle, and read off the point where it meets the underside of the arm.

Two things to watch. First, the arm is not flat - it usually curves down toward the needle end, so take the reading at the lowest point of the arm, not the roomiest. Second, if your machine has a removable free arm cover or an extension table, measure with the setup you actually quilt in.

This is the number almost nobody has and the number that decides whether a quilt fits. A rolled quilt is a cylinder, and a cylinder that will not clear the height does not care how much width is waiting for it.

Turn the two numbers into one

Why your number will not match the published one

Expect to be within about a quarter inch, and do not worry if you are not exactly on it. Three reasons the figures drift:

The reference point. Makers measure from the needle center or from the needle’s right-hand edge, and they do not usually say which. That is a few millimeters on its own.

The height reference. Some figures are taken from the needle plate and some from the bed surface, which sit at slightly different levels.

The convention. This is the big one. Brother publishes the PQ1600S as “5.7″ x 8.7″ needle-to-arm space” - height first - while publishing its embroidery work areas width first, with nothing on the page saying which is which. If you are checking your measurement against a spec sheet, work out which number is which before deciding you measured wrong. Every figure on this site is normalized to width by height with the maker’s original wording recorded beside it.

Where your machine sits

Once you have your figure, this is the company it is in. Every row is a published manufacturer figure, normalized to width by height:

If your own measurement lands near the bottom of that table, an upgrade is a real change rather than a marginal one. If it lands near the top, more room is not your problem and you should spend the money elsewhere.

The other measurement worth taking

Roll up the largest quilt top you own, as tightly as you would to get it under the machine, and measure the diameter of the roll.

Now compare that with your height figure. If the roll is thicker than the opening is tall, the quilt is not going through, and no amount of extra width will change that. That single comparison answers the upgrade question faster than any specification sheet, and the sizing rules of thumb are on how much throat space you need.