How to Measure for Oversized Frames: A Practical Guide

Getting a custom oversized frame made for your favourite artwork or print can be exciting, but it starts with spot-on measurements. One small slip-up and the whole thing might not fit properly, leading to headaches down the line. We've been building bespoke frames at Harten Frameworks for decades, often for large pieces that need extra care, and we've seen what works best from countless customer projects.

Why getting the measurements spot on really matters

Oversized frames aren't off-the-shelf items. Everything gets cut and assembled specifically for your piece, including the frame itself, any glazing, mounts, and backing. The dimensions you give us determine the internal space (called the rebate) where your artwork sits. If it's off even a little, the art could be loose, too tight, or not sit securely. With custom work like this, production starts right away, so there's no easy swap if something's wrong. Taking time upfront saves a lot of trouble.

What you'll need

Grab a sturdy metal tape measure – the retractable kind works great because it's rigid and accurate. You'll also want a clean, flat surface big enough to spread out your artwork without any curling or bending. Have some paper and a pen handy to jot things down. If the piece is heavy or awkward, ask someone to help steady it. Skip fabric tapes; they stretch and can throw things off.

How to take the measurements

Start by laying your artwork face up on that flat surface. Smooth it out completely – no bumps or curled edges.

First, decide what type of artwork you're dealing with, as the approach varies a bit.

For prints, photos, or flat paper pieces: Measure the full width (left to right) and height (top to bottom) right to the edges. Do this in a few spots – top, middle, and bottom for width, and sides for height – in case it's not perfectly even. Use the largest numbers if there's any difference.

If your print has a white border you want fully visible, include it in the measurement. If you're planning a mount to overlap the edges slightly (common to hide any imperfections), measure just the image area you want showing.

For stretched canvases: Again, lay it flat and measure the front face from edge to edge at several points, taking the widest and tallest. Canvases can warp slightly over time, so checking multiple spots avoids surprises. Also measure the depth (thickness) of the stretcher bars along the side – this ensures the frame's rebate is deep enough.

If your canvas is irregular or quite thick, a floater frame might be worth considering. These sit around the canvas with a small gap, showing the edges without any overlap on the front.

Whichever type, always measure in millimetres for the precision we need in the workshop. Width comes first, then height – so something like 1200mm x 900mm.

Double-check everything at least once. It's quick and catches most errors.

A bit about how frame dimensions work

People often wonder about the visible area once framed. The internal rebate matches your exact artwork measurements so it slots in snugly. From the front, though, the frame's inner lip usually overlaps the edges by a few millimetres to hold everything securely in place. That's standard and keeps your piece safe without slipping.

Adding a mount

A mount (that's the card border around the artwork) creates breathing space and really elevates the look. If you want one, think about how wide you'd like it on each side – typically 50-100mm or more for oversized pieces to balance things out. The overall frame size then becomes your artwork dimensions plus twice the mount width on both height and width. We can advise on options that suit your piece best.

If measuring feels tricky

Large or valuable items can be nerve-wracking to handle yourself. Many customers ship their artwork to us, and we measure professionally in the workshop before quoting and framing. It's often the safest route for fragile or heavy pieces.

We're always happy to chat through your project early on and guide you if needed.

A few extra pointers from experience

Measure in a well-lit spot and keep the tape straight and level. Don't add any extra allowance – just give the true sizes. Avoid guessing from old labels or generic charts; artwork can shift over time.

If you're ever unsure, just get in touch. You can send the piece to us for accurate measuring and a proper quote, then we'll frame and deliver it ready to hang.

Nailing the measurements means your oversized artwork gets a frame that fits perfectly, looks stunning, and protects it for years. We've helped with thousands of projects like this, and it's always worth that bit of care at the start.