DateField: monospace font

[ValeraS]

Objective

Currently, DateField uses proportional (non-monospace) font. In proportional fonts, digits and separators can have different widths (and widths can vary across digits), so the caret and surrounding text shift as you enter or edit values. That “jumping” feels glitchy.

Screen.Recording.2026-02-10.at.11.17.46.mov

Also proportional font makes it difficult to set an input width that fits content. The CSS property field-sizing can help, but browser support is limited.

Solution Proposal

Using a monospace font keeps the input visually stable.

Screen.Recording.2026-02-10.at.11.19.09.mov

It also makes it easy to keep the input width in sync with its content using the size attribute.

Native <input type="date"> uses monospace font.

[ykamendrovskiy]

Some thoughts on the matter

1. We've got to make sure whether this solution should become a default or a sort of CSS API extension (probably suitable for other input-like controls as well)
2. We've got to make sure whether DateField with a monospace font would fit other controls in big forms
3. Another thing to decide is a font to use for a label attribute

@ValeraS @korvin89