Tell him you want to get him something that he’ll wear, but that you don’t want to spoil the surprise. Then go and measure him in a bunch of different places. He’ll know he’ll be getting some sort of item of clothing or apparel, but he won’t know whether he’s getting shoes, a shirt, a watch, or a ring.

just measure his dick and extrapolate from there

Cut his arm off in his sleep with a machete. While he’s rushed to hospital and they stitch his arm back on, sneak out with his watch.

deleted by creator

Most watches come with removable links. So they can be retrofitted. And chain style bands are adjustable.

Just take one of his other watches to the shop and ask them for one the same size.

Does he have dress shirts in the closet? The cuff should fasten comfortably around the wrist and not slip over the width of his palm, right?

I did this for my girlfriend, now wife.

Do it while he’s sleeping. If he wakes, gaslight gaslight gaslight.

Get a friendship bracelet kit for funsies. These are the bracelets where each bead is a letter, a heart or a cheap plastic thing. Tell him “I’m making friendship bracelets to put in the stockings for Christmas. I need to practice on you” Make him one. Tell him not to shower with it because the metal is bad quality. You now have his wrist size.

You can also memorize the bracelet order and aragement of the beads and make a copy when he’s gone.

If he’s a heavy enough sleeper you can wrap a string around his wrist and mark where it meets to get a close estimate and then talk to a jeweler about what that corresponds to

Before we go any further, how tight does your husband wear his watch? To a lot of people it’s really particular. If we’re guessing use a string and try to match his current habits, if not have a slightly taught string around his wrist and measure.

Or borrow his current watch.

Alternatively, get him a watch and a little tool kit to resize it himself. My smartwatch came with a resizing tool kit and I love that little hammer which I can use to bang out the pins and resize it. Only needed to do it twice till now but so glad I had the option to do it myself rather than having to get a jeweler to do it.

Little hammers are fun!

Does he wear a watch usually? You could measure that if so.

Even if it’s not a fixed size, you could tell by the wear on the band what the size is

First, try love handcuffs on him and note how they fit.

Does he wear a watch now? Does he ever take it off? Snap a picture top down on its side and put a ruler in the picture for reference. Measure the watch circumference with a piece of string and then flatten it out on a ruler. Keep the string by the bed and wait for him to fall asleep and measure his wrist like that. Suggest using handcuffs in the bedroom and surreptitiously measure the wrist that way.

Somebody else suggested you measure everything about him. Waist, legs, cuffs, etc. That’s a good idea as well.