You know this tip, don’t you? When you tap the Space bar, the web page you’re reading scrolls up exactly one screenful.

That’s so much quicker and more precise than trying to use the mouse or the trackpad. When you’ve read to the bottom of the screen, hit Space to scroll. (Press Shift-space to scroll back up.) Works in every browser, on every site.

For this tip to be useful, of course, the amount of scrolling is important. The last line you’ve read (at the bottom of the page) should jump up to become the top line of the new screen. Like this:

(If you prefer, you can use the Page Down key to do the same thing. One tap, one screenful.)

But in recent years, something clumsy and unfortunate has happened: Web designers have begun slapping toolbars or navigation bars at the top of the page. That’s fine—except when it throws off the Space-bar scrolling! Which, most of the time, it does.

Suddenly, tapping Space doesn’t scroll the right amount. The lines you were supposed to read next scroll too high; they’re now cut off. Now you have to use your mouse or keyboard to scroll back down again. Which defeats the entire purpose of the Space-bar tip.

Here’ what it looks like on one of these broken sites:

Over the last few months, I’ve begun keeping track of which sites do Space-bar scrolling right—and which are broken. I want to draw the public’s attention to this bit of broken code, and maybe inspire the world’s webmasters to get with the program. It can’t be a complicated fix—but for something that millions of people do billions of times a day, it seems as though it’d be effort well worth expending.

So here it is: The world’s first Space-Bar Scrolling Report Card for the biggest reading sites of the internet.

Sites that scroll correctly

Sites with broken scrolling

Here’s what I propose: We, the people, should spread the word of the space-bar trick, because it’s precise, it saves time, and it makes for easier, more continuous reading. And uninterrupted reading = better understanding.

They, the web programmers, should get their act together so that the scroll works as it’s supposed to.

(And if you work for one of those sites, and you manage to get the scrolling-bug fixed, email me so I can update this article and congratulate you.)

Thank you. This has been a public-service message.