Upload fonts
For the converted design to look right in the live preview, it needs access to the fonts you use. Google fonts are automatically uploaded to the live preview.
If you use other fonts, the live preview asks you to upload the font files. You only need to upload each font once as the live preview stores it until you clear the browser cache.
To make the fonts permanently accessible accross all your designs, upload them to your Qt Account.
Upload fonts to the live preview
To upload fonts to the live preview:
- In the live preview, go to
(Fonts) > Active project.
Uploading fonts to the live preview.
- Drag
.ttf,.otf, or.wofffiles to the page, or select Select files to browse the file system for the files.
Save fonts to your Qt Account
To permanently store font files, log into your Qt Account or create a new account.
To save fonts to My fonts:
- In the live preview, select
(Fonts) > My fonts.
Uploading fonts to Qt Account.
- Select Log in to log into your Qt Account or to create a new account.
- Drag
.ttf,.otf, or.wofffiles to the page, or select Select files to browse the file system for the files.
If you run out of storage page, remove obsolete fonts.
Manage Google fonts
To turn off the automatic uploading of Google fonts, select
(Settings) in the live preview and turn off Automatically upload Google fonts.

Live preview settings.
Use the Spark font engine on Qt for MCUs
Qt for MCUs offers two font engine options:
- Static engine for simple text applications with known character sets, minimal memory requirements, and maximum performance.
- Spark engine for internationalized applications that have complex scripts (such as Arabic, Hindi, or Thai) or bidirectional text or need dynamic text rendering.
The Static engine is the default option. It requires font files to be listed in the project configuration.
To add a setting to the QML project file to use the Spark engine, go to
(Settings) > Code in the plugin and then select Spark font engine for text rendering.

Code settings on the Settings page in the plugin.
The Spark engine supports a single file at a time. The file can be one of the following:
- A fontmap file (multiple fonts combined into a single file)
- A single
.ttffont file (that is, one font)
If your design uses only a single font, you can use the font file directly without going through the steps to create a separate fontmap file.
See also Preview converted designs and Download converted designs.
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