NICETOWN Thermal Insulated Curtains, 2 Panels, W42 x L84-inch, Silver Grey

These are NICETOWN's standard thermal blackout curtains. Across all sizes and colors the listing has around 133,000 reviews and a 4.6-star average. A pair of 42 x 84 inch panels in silver grey costs about $36, and other sizes and colors are priced differently.

How dark they get

NICETOWN says these block 85% to 99% of light, and that darker colors do better. The word "blackout" on the box therefore needs a footnote. A navy or black pair will get close to dark. A light grey or beige pair will leave the room dim, not dark.

There's no separate liner. The darkness comes from a triple-weave fabric, which keeps the panels soft and lets them go in the washing machine (cold, then tumble dry). Lined curtains usually can't.

Light also gets in around the sides and over the top of any curtain, whatever the fabric. Our best blackout curtains guide covers overlap and rod placement, which matter about as much as the fabric does.

Hanging them

Each panel has six grommets with a 1.6-inch inner diameter, so they slide onto a standard curtain rod with no hooks or rings. The listing says they arrive thread-trimmed and wrinkle-free.

Other things the listing claims

Some insulation against summer heat and winter cold, some noise reduction, and less sun fading on floors and furniture. Heavy fabric does help a little with all of these. Just don't buy them to fix a drafty window or a loud street.

Who they're for

• Most bedrooms where you want the room much darker and can live with a sliver of light at the edges
• Kids' rooms and guest rooms, where being able to machine wash them matters
• Anyone who wants a darker color and doesn't need total blackout

Who should skip them

If any light at all wakes you, or you sleep through the day after a night shift, look at the NICETOWN 100% blackout lined curtains. Two layers of fabric with a black lining get you closer to fully dark, though they're hand wash or dry clean only. Our blackout blinds for shift workers guide goes further on daytime sleep.

Renters who can't put up a rod can use the Amazon Basics portable blackout shade, which sticks to the glass with suction cups.

To cover the edges too, pair the curtains with a shade. Our guide to light blocking blinds for the bedroom explains how. Closed curtains also keep some afternoon sun out in summer, and how to cool a bedroom without AC has more on that.