Regarding units to use and design: Yes, DPI is definitely a problem when it comes to designing web sites. More information can be found in: Resolution vs. browser size vs. fixed or adaptive width.

Can you provide one or two helpful links on where to get started understanding this issue in detail?

More and more Windows machines are set to ‘120 DPI’ and that increases font sizes, which breaks website designs, and also increases images sizes, for which there seems to be no fix at all!

Thanks.

That the defaults are too big is an argument with a genesis in the mid ’90’s, when the default was 640×480, 800×600 was frequent, and 1024×768 was very rare. In those conditions, when the windoze 96 DPI default was conceived and applied to screens of under 50 dpi, making the default 12pt 50% bigger than 12pt print, the defaults were indeed usually too big, and quite ugly due to the pixelation and jaggies of low resolution. This is no longer the case over 10 years later. 1024×768 is the new standard, including a large proportion of 13″-14″ laptops no larger than the CRTs of 640×480 days; 640×480 is history; 800×600 is fast becoming history; and high resolution of 1280 wide or higher, including for 16″ or smaller laptops, is now and the future.

What the absolute size default is that a user prefers is simply irrelevant in a good accessible web page design. It just happens to be that 12pt is what users most commonly prefer, and on average what they’ll get from web pages with no text styles in today’s environments.

Doze still defaults to 96 DPI, and often that is actually close to accurate now (not infrequently erring in the other direction), making the IE 12pt default pretty much what most users prefer on average. This table shows 96 can now be pretty close, or even go under. Laptops are now often configured reasonably at 120 DPI by their vendors. This means the IE 12pt default is more likely close enough to what users want than what any arbitrary CSS adjustment you apply can hope to achieve.

The style properties of the font will affect perception though it would be too narrow to assume that size is the major factor with readability, it depends what you want to add colour and spacing of letters, lines and the wetware factor, etc.

One could produce a black and white website without any CSS and it would be pretty much inaccessible to a large proportion of users.

I myself have disability and don’t find the ‘Useit Alertbox’ legible; admittedly it does use CSS and focuses on Web Usability. Also many people wrongly think “Style Switchers” help accessibility, whereas in most cases they actually confuse the user.

There were one or two contradictions you made with the last post but we’d be swaying off-topic too much. It also wouldn’t matter if the text size was 200px I’d still would have issues reading it.

Anyway it was fun discussing the topic.

As I expressed above, I don’t entirely agree. Like I said, I find it to be a compromise of different goals, and trying to make the best out of it.

Given that a mjority of the web users have the medium text setting and also that they don’t even know how to change this, to get a text size that looks good designwise, you’ll want to decrease the font size.

Then I think it also comes down to the tools, i.e. the web browser manufacturers, with features like zooming.

Size, brightness, and contrast are basics. If you can’t get them right, there’s little more you can do for most people, people who have no problem reading as long as text is at least the size they require. Poor legibility is the #1 web user complaint. Fully accessible pages do not produce that complaint.

Nyman, I’m not at all saying no designer should ever size text. I’m saying designers need to know the consequences of what they’re doing, and understand why and for whom they’re doing what they’re doing. There’s no good reason they can’t style to suit every personal whim if they’re only designing to please themselves and/or other web designers, all of whom are not normal web users. Designers certainly have the power to produce pixel perfection for the environment they’re using to do their designing.

However, the environment of the visitor is an infinitely variable unknown. The web is an inherently fluid and adaptable medium. The designer doesn’t know the display size, resolution, viewport size, visual actuity, or other user local factors that determine what works acceptably for each user.

A designer designing for the majority of the planet’s users needs to embrace the fluidity that is the essence of the web. This requires building adaptable pages, pages that can and do work for the visitor regardless of his local variables. Adaptability is accessibility.

Small text is for legalese. Big type is good business. Browser makers give users adjustable defaults precisely so users can determine in advance of reaching your page how big is big and how small is small.

You as designer can’t actually know what size any particular visitor’s default is, so you must make sure your design doesn’t depend on some particular size, instead, working well whether the default happens to be 11px, 3cm, medium, largest, smaller, 24pt or anything else that fits reasonably in the viewport of whatever reasonably sized visual device the user happens to be using.

The user’s actual default size shouldn’t matter to anyone except the user, so arbitrarily setting a size for normal P content at 75% of whatever it happens to be serves no purposes other than barring some users, impeding other users, and keeping people who have sampled the web and found it too difficult from trying again. It limits/reduces accessibility.

As in print, contextual text sizing for the web is a valid means of communicating. But text sizing by the designer should be restrained by the designer himself to applying user default based contextual (relative) sizing only to things that need it, like headings, sidebars, breadcrumbs, footers and such, leaving content P text, the basic or dominant size, at the user default. In the overwhelming majority of cases, if the designer thinks his design requires a smaller base size text, then either his own browser default is wrong, or he’s not designing for most of the web’s users.

Likewise it would be folly to assume size and contrast were the main barriers to reading text. Though I agree it does need to be legible. For example blue body text containing blue hyperlinks isn’t always legible.

Like Robert said theoretically: User Agent Accessibility Guidelines (UAAG) is there to that help lower barriers to Web accessibility obviously the M$ browser seem to disregard some of them.

We know Video Systems know no concept of DPI at all and only work upon pixels. As you will notice that the word “dpi” simply does not appear in any user manual for any monitor or for any video board 96 dpi setting in the Windows video settings is called “Font Size”.

Though I agree you have to be careful to make sure you don’t accidentally add too many barriers to a website.

Correct me if I’m wrong here, but are you saying that no designer should have the possibility to decide what text size is best suitable and consistent with the rest of their design (e.g. a smaller font in a sidebar listing than the default in the web browser)?

In that case, it rather sounds like accessibility trumps and holds back design. I don’t think we will ever have a web where every web site per default has got a consistently large (and in many peoples’ opinion oversized) font no matter what design is being used, just to have it a 100% according to web browsers’ default font size.

Personally I think it’s ok to have a font that would, for example, be equivalent to 10 pixels if it suits the design, but then that it’s naturally resizable as well. That way we get the compromise of the two worlds, without holding design or accessibility back (except for the mentioned IE problem above, of course).

First, I definitely don’t declare myself as an accessibility expert; I plainly express my personal opinions from my experience.

And while I get your point, there are several factors I want to mention:

1) First and foremost, not being able to get larger text than it’s possible in Internet Explorer is a shortcoming in IE. Then if it’s dad’s responsibility to use a web browser that gives him more possibilities or not, I’m not sure.

2) This is a classic example of clash between classic accessibility and everything else one wants to accomplish with a web design. If one wants the default font size to be equivalent of around 12 pixels with the normal text size setting (that a majority of users have) it needs to be scaled down from web browsers’ default 16 pixels, but then naturally with the possibility to resize it.

3) Take whatever major web site that is released: there will be design guidelines how large the default font should be for a majority of the visitors. It’s not about my or any other person’s personal preference, it’s about what will look the best for the target audience. Of course I know this is a compromise and not the best option for IE users that need a very large text setting, but it is a deliberate design decision. At least the font here in my web site is resizable at all in IE, as opposed to most web sites out there.

Conclusively, IE is the only web browser that doesn’t offer pretty much unlimited text resizing, and that will change with the zoom feature in IE 7. So while I acknowledge the problem, I’m happy to see that it’s one that will go away.

Here’s why your 75% font-size is too small, even with your 1.5 line-height and white on black P text:

Dad has typical senior eyes. He can read, but not as well as he used to. As much as possible he reads only books in large print editions. He struggles to read the small print in most newspapers and magazines. He buys a 17″ flat panel to replace his 15″ CRT, thinking that 3″ actual difference going to make everything bigger and easier on the eyes. He gets it home, and finds its instructions recommend using its native resolution for best results. That’s 1280×1024, and he’s astonished to find unstyled web page text is actually smaller before.

What happened? It turns out that he needs 14pt type to read web pages comfortably. Due to the error of applying 96 DPI on a 14″ CRT screen, which in fact is only 91 DPI on the median 1024×768 resolution he was using, his IE 12pt default was actually only slightly less than 14pt. Now with a smaller error applying 96 DPI to a larger screen that is in fact 94 DPI at its native resolution, the default 12pt is smaller instead of larger. The quality is better, but that doesn’t make up the difference, so he manages to find the IE text resizer, and finds that the larger setting gives him the approximately 14pt size that works for him, and many other senior adults. How should text be presented within a website?

Now he comes to your 75% page and finds his 14pt text turned into 10.5pt text. So, he goes and finds that IE text resizer widget again, and changes it to the largest available choice, and guess what, he gets maybe 12pt, and that’s too small for him to read comfortably on his fancy new larger display. In the top IE window of this screenshot is what he sees. He doesn’t know every browser he’s never heard of can give him what you should have given him in the first place, shown in the firefox window underneath.

So, it doesn’t matter that you size in ems or keywords or % if you’re usurping your visitor’s decision what size works for him with an arbitrary reduction from whatever that choice happens to be. It’s rude and unwarranted. If you think your browser default is too big, then change your own browser default, and don’t mess with dad’s. He’s probably where you’ll be in 20-30 years, and you won’t like it any more than he does.

With setting the font with the em unit, it will adapt to the users text size setting in their web browser. As you can see in my CSS file, the basic setting of the font is 100% of the default font setting (normally about 19 pixels), and then making the general font respectively smaller since I don’t want a minimum of 16 pixels font on all pages (something I think you agree on).

Siegfried,

To me it’s about where you draw the line with accessibility. If you from the start write correct semantic code, separate CSS and JavaScript from the HTML-content it doesn’t take longer to develop such a web site.

When it comes to web designers and companies, I think it’s their responsibility that they know how to do the job correctly in the first place.

Where some factors of accessibility can take longer time is in the test phase, if one will want use tools as screen readers etc.

Most likely important steps to enlightenment! Good luck!