How do you increase font size/scale?


Ive looked at:


but I’m still not sure what to do here.

I’ve enabled #define LV_FONT_ROBOTO_28 1 in lv_config.h and added the following into my code:

` static lv_style_t st;
lv_style_copy( &st, &lv_style_plain );

st.text.color = LV_COLOR_WHITE;
st.text.font = &lv_font_roboto_28;
lv_label_set_text(label, "22:30");
lv_obj_set_style( label, &st );


but my font size is still tiny. See attached photo.

Is there any way to scale these up so they are 5x to 10x bigger?

Thanks in advance

Hi Alex,

I need to generate a new font.
The most simple way is to use the Online converter. You can find the required instructions are on the converter’s site.

Thanks for the info.

I downloaded the Roboto font from:

and tried to convert it but got the error:

TypeError: Cannot read property ‘source_path’ of undefined

Any idea what i am doing wrong?


Please provide a screenshot with the settings you passed to the converter.

As requested:


You haven’t filled the range. Try 0x20-0x7F for the ASCII range.

Yay, that worked!

You may want to put some validation on that field to prevent anyone else falling into the same trap thinking it would default to ASCI.

For anyone else using the converter and get the following:

sketch\Roboto_80.c:1:23: fatal error: lvgl/lvgl.h: No such file or directory

#include “lvgl/lvgl.h”

#include “lvgl.h”

in the c file produced.


The more correct way to do it (which does not involve modifying an autogenerated file) is to add the parent directory of the lvgl folder to your include path.

Good idea. I can add it (if I remember). :slightly_smiling_face:

Unfortunately the Arduino implementation (on Windows at least) doesnt have a lvgl folder.


Good point. I didn’t know you were using Arduino.

I’d suggest instead of manual operations use CLI and add to your script sed call to make replacement:

That simplifies reproduction and helps to avoid errors next time.

I use the lv_font_roboto_28 font style, but exxeption occurred

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