Blueink eSignature API vs OpenSign
Blueink eSignature API
developer.blueink.com
OpenSign
opensignlabs.comSide by side
| Figure | Blueink eSignature API | OpenSign |
|---|---|---|
| Price from | $90/mo | $9.99/mo |
| Free plan | — | Yes |
| Free trial | Yes | Yes |
| Open source | — | Yes |
| Web | Yes | Yes |
| Windows | — | Yes |
| macOS | — | Yes |
| Linux | — | Yes |
| API | Yes | Yes |
| Self-hosted | — | Yes |
| Plans published | 7 | 5 |
| Spec score · E-Signature APIs Software | 8.3 (#7) | 9.0 (#3) |
| Spec score · Electronic Signature APIs | 8.2 (#10) | 8.9 (#2) |
| Integrations | Blueink lists integrations including Airtable, Dropbox, Gmail, Google Drive, Google Sheets, HubSpot, Salesforce, Slack, and Zapier. | The Professional plan lists Zapier integration, Dropbox import and custom Gmail or SMTP sending. |
| Intended users | Blueink describes its API plans as intended for developers and businesses integrating eSignature into products or applications. | The documentation describes the product as designed for individuals and businesses, from startups to large corporations. |
| Security | Blueink states that its transactions are end-to-end encrypted, data is encrypted at rest, and access controls follow least-privilege practices. | The API documentation lists TLS-encrypted transport, audit trails, IP logging, and tamper-evident signed PDFs. |
| Support | The API plans list email and chat support, and Blueink describes dedicated API technical support during testing. | The documentation directs users to contact OpenSign support at [email protected] for assistance. |
Plans
Blueink eSignature API
- Bronze (annual)$90 a month
- Bronze (monthly)$108 a month
- Silver (annual)$240 a month
- Silver (monthly)$288 a month
- Gold (annual)$480 a month
- Gold (monthly)$579 a month
- EnterprisePriced on request
OpenSign
- FreeFree
- Professional$9.99 a month
- Teams$19.99 a month
- FreeFree
- EnterprisePriced on request
In their own words
Blueink eSignature API
Blueink eSignature API has no write-up on Specifiction yet; its figures are above.
OpenSign
OpenSign is an open-source PDF e-signature solution for signing, storing, and securing documents. Users can create reusable templates with pre-placed widgets and send them through the API to one or many signers. API workflows include self-signing, drafts, signer roles, public template links, and real-time webhook notifications. Templates can be embedded in React, Next.js, HTML, JavaScript, and Angular projects. The documentation lists TLS-encrypted transport, audit trails, IP logging, and tamper-evident signed PDFs; account protection includes two-factor authentication and passkey sign-in. The free plan costs nothing and lists unlimited digital signatures and templates, completion certificates, sequential signing, OpenSign Drive, and email notifications. Its free-plan guide limits invitation emails to 15 per month; bulk sending and public links require a paid plan. Live API tokens require Professional or Teams, though sandbox tokens are available on all plans. OpenSign provides Docker self-hosting instructions for Linux, macOS, and Windows. Some SMTP features are limited to paid plans.