Both SignProof and Dropbox Sign (formerly HelloSign) offer clean signing APIs. Dropbox Sign is a mature, developer-friendly product tightly integrated with Dropbox. SignProof is an independent, API-first alternative with transparent self-serve pricing and a free tier that includes full API access.
Dropbox Sign and HelloSign are trademarks of their respective owners. Comparison is for informational purposes; check current pricing and features on each vendor's site.
Yes, especially for developers who want transparent self-serve pricing and a free tier with full REST API access. Both SignProof and Dropbox Sign offer clean signing APIs; SignProof is an independent service with a single-seal PKCS#7 integrity model and a hash-chained audit log, built for PIPEDA, ESIGN, and UETA.
Dropbox Sign (formerly HelloSign) is a developer-friendly product owned by Dropbox, with strong embedded-signing and storage integration. SignProof is an independent, API-first service with transparent published pricing, a free tier that includes full API access, and a tamper-evident PKCS#7 seal plus hash-chained audit trail.
SignProof offers a Starter plan that is free forever and includes full REST API access, PKCS#7 sealing, OTP identity verification, and webhooks, with 5 envelopes per month. Paid plans start at $9/month (Solo), with unlimited envelopes from $29/month (Pro).
See also: SignProof vs DocuSign · Best e-signature APIs