Win 11 - Is it possible to make the system font bolder?

Windows uses ClearType fonts, which give you the ability to make the font a little thicker and heavier, but not very thick or heavy. Look here:

Start > Settings > Personalization > Fonts > Adjust ClearType text

Hello， Nonie123

Thank you for posting in the Microsoft community.

I understand that you would like to set the thickness of your Windows 11 system fonts so that they are easier to read, but as far as we know there is no setting on the system itself that allows you to adjust the thickness of the fonts. However, Microsoft takes every user's voice seriously, you can submit your ideas and suggestions through the Feedback Hub, and the development team will regularly review submissions for ideas or fixes. 

Please share the feedback link here after submitting as it will allow others on the forum to vote for your submission, including me. More votes will lead to more visibility and higher priority to the development team.

Best Regards，

Rota Ye |Microsoft Community Support Specialist

Thank you, Chien. I did know about that, but it seems to do nothing. It shows comparisons of text blocks that look practically identical to me. Do you think it makes any difference at all? Maybe it's just me.

Thanks for your suggestion. I submitted it under Accessibility Settings. I couldn't sign in to track it, though, unless I wanted to activate some kind of Hello thing or some such nonsense, so I guess I won't be able to follow it. Oh never mind, I get it now, that's just a Microsoft way of saying it will remember my sign in credentials for me. Sheeesshhh ;)

Do you think it makes any difference at all? Maybe it's just me.

It's true that everyone perceives a font differently. Also, the appearance of a font is influenced by ambient lighting and by the darkness or lightness of the background. Sometimes increasing the size of text, even a little, makes a big difference.

There are some controls in Start > Settings > Accessibility that might help.