DocuSeal

DocuSeal is an open-source document signing platform that turns PDFs, Word files, or images into fillable forms with a visual field builder, then sends them out for legally binding electronic signatures. Templates support several signer roles, along with date, text, checkbox, and signature fields, automated email invitations and reminders, and a REST API with webhooks for wiring it into other systems.

Sales, HR, and legal teams use it for contracts, offers, and consent forms, and developers embed the signing flow in their own products.

Self-hosting keeps signed files and signer records on servers under your control and avoids per-envelope fees.