How to Size a Shower Curtain? | Measure Right, Buy Once

Measure your shower opening’s width and add about 12 inches, then measure from the rod down to 1–2 inches above the floor or tub edge.

Whether you’re dealing with a shower curtain that pools on the floor or one that leaves a gap for water to escape, getting the size right starts with two simple measurements. Getting the dimensions wrong means a return trip to the store, so here’s the exact process for a curtain that fits like it was made for your bathroom.

How To Measure Width For A Shower Curtain

Your first measurement is the width, and this is where most sizing errors start. Grab a tape measure and stretch it wall-to-wall across the shower opening — if you have a curved rod, measure along the rod’s arc rather than straight across, since the curve effectively widens the span.

Take that opening measurement and add roughly 12 inches. That extra width creates the gentle bunching you see on properly hung curtains, ensuring no gaps at the edges when the curtain is pulled closed. The result is your ideal curtain width.

Here’s the most common width mistake: measuring only the rod itself. If your rod extends beyond the opening, measure the actual opening space, or you’ll end up with a curtain that’s too wide.

How Long Should A Shower Curtain Be?

For length, measure from the rod down to where you want the curtain to end. The key difference from width: don’t measure from the ceiling — the rod height is what sets the hanging length. For a standard tub shower, your curtain should hang into the tub by about 6–10 inches to properly contain water, while ending 1–2 inches above the floor is the goal for a shower stall.

Now the detail everyone forgets — hardware alters the drop. If you’re using rings or hooks, measure from the bottom of those rings or subtract their drop from your rod-to-floor number. Hookless curtains, which have built-in grommets that sit directly on the rod, measure from the top of the rod instead. Skip this step and your “perfect” length curtain will hang a few inches too low.

Standard Shower Curtain Sizes To Know

Most manufacturers stick to a handful of standard dimensions. A quick note is worth adding here: the liner should match your curtain’s size or run slightly smaller so it doesn’t peek out from behind.

If your measurements fall outside these ranges, custom options and “90-inch” curtains exist for taller setups. For a rundown of the best extra-long options on the market, see our guide to the best 90 inch shower curtain picks.

Avoid These Shower Curtain Sizing Mistakes

The most common sizing errors are easy to avoid once you know what to look for. Here’s where people trip up:

• Measuring from the ceiling: Always measure from the rod, because that’s where the curtain physically hangs.
• Ignoring ring and hook drop: A curtain that fits perfectly with a hookless design can drag on the floor when hung from rings. Account for the hardware before ordering.
• Choosing too short: If the curtain barely reaches the tub edge, water splashes straight out onto the floor.
• Letting it pool too long: A curtain dragging on the floor isn’t just a tripping hazard — it soaks up standing water and becomes a magnet for mold and mildew.

When in doubt, ordering slightly longer gives you more flexibility since fabric can be hemmed. A curtain that’s too short offers no easy fix. Keep your wall-to-wall measurement, add 12 inches of fullness, and measure down from the rod — not the ceiling — and you’ll nail the size on the first try.