Creating stitch charts

Hello, could someone please help me?
I’d like to create a knitting pattern (stitch chart) on my computer. Is there a suitable program or app that can help with this, for example, by providing a grid and/or graph paper? I’m NOT referring to apps that help you create a pixelated image from a picture or photo. So far, I’ve been creating my stitch charts by hand—it’s time-consuming, and I can only use them for myself. But through this forum, I could share my ideas with you all if I can figure out how to convert the paper draft into an “online format.” 
Thanks for your help.
Best regards to everyone

I use the program Stitchmastery. It does cost money, though.
Otherwise, I would just create simple charted patterns in Excel. Maybe that’s worth a try?

I create my knitting charts in Excel. For my symbols (knit stitch, yarn over, knit two together, etc.), I use the "Marlett" font.

My customers and I manage quite well with that.

I’m currently on the wrong computer, where I haven’t saved any of this. Stitch Fiddle has a free and a paid version for knitting and crocheting and is very easy to use. Then there’s another one—I think it’s called Knitting Chart Generator—that works well for simpler knitting charts. And there’s one more, but I’ll have to look that up tomorrow on my other computer.
You can also download grid paper and graph paper—if I remember correctly, you should be able to find it under “Graph Paper.”
If you’re willing to spend some money, Stitchmastery is definitely an option. 

Thank you very much, I think your answer will help me. Best regards