> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/web/get-started/guides/samples/forms.md).
# Samples to customize PDF Forms with JavaScript
Discover how to add form fields to a PDF with this Form Builder Demo. Learn to customize signatures, text fields, and checkboxes. Change color and opacity easily. The Apryse Web SDK streamlines secure
## Form Builder Demo
This sample demonstrates how to add form fields to a PDF. Fields are first added as annotations and then converted to interactive form fields. Add signatures, text fields, checkboxes.
Launch demoView source code
## Customizing form fields
Shows how to change color and opacity of form fields.
Launch demoView source code
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