eSignature API for Modern Developers
Build seamless, secure, and compliant document signing workflows directly into your application. Review API access, explore the documentation and plan your signing workflow.
An API Built for Performance and Scale
Stop wrestling with complex integrations. The eSignly API is designed from the ground up to provide a seamless developer experience, enterprise-grade security, and unmatched reliability.
Superior Developer Experience
Get started in minutes with our clean, intuitive REST API, comprehensive documentation, and interactive examples. We prioritize clarity so you can focus on building, not debugging.
Reliability & Service Terms
Plan for availability, retries and recovery in your document workflows. Confirm the service terms and any applicable SLA for your chosen API plan before production use.
Ironclad Security & Compliance
Security isn't an afterthought; it's our foundation. We are compliant with SOC 2, HIPAA, GDPR, and more, providing bank-grade security for every transaction.
Transparent, Predictable Pricing
Review current API plans for usage limits, pricing and testing access. Confirm the billing unit and any additional requirements for your integration before choosing a plan.
Built for Hyperscale
From one signature to millions, our infrastructure is designed to handle your peak loads without breaking a sweat. Process high volumes of documents with consistently low latency.
Comprehensive Feature Set
Go beyond simple signatures with features like embedded signing, templates, bulk sending, webhooks for real-time updates, and detailed audit trails for every document.
Plan Your API Integration in 3 Steps
Review the documentation and API plan requirements, then test your workflow before enabling production requests.
Review API Access
Review API plans and the authentication documentation. Confirm how to obtain credentials and which testing environment is available for your account.
Does not require any SDK
Use our REST APIs with your preferred programming language to easily authenticate and make API calls.
Send Your First Request
Use a few lines of code to upload a document and send your first signature request.
--form 'api_key=YOUR_API_KEY' \
--form 'template_key=YOUR_TEMPLATE_KEY' \
--form 'signer_role[0]=manager2' \
--form 'signer_email[0][email protected]' \
--form 'title=Contract Signing' \
--form 'subject=Please sign the document' \
--form 'message=Kindly review and sign the document.' \
--form 'api_domain=https://yourdomain.com' \
--form 'redirect_uri=https://yourdomain.com/sign-complete'
Powerful API Features & Use Cases
Discover how our flexible API can power your most critical business workflows, from customer onboarding to internal approvals.
Explore related capabilities: Agreement Workspace, Contract Intelligence, and the MCP guide for agreement workflows.
Workflow code below is illustrative. Use the API documentation for current endpoints, authentication and request parameters.
Seamless In-App Experience
Keep users inside your application with our embedded signing feature. Customize the signing flow to match your brand's look and feel, creating a frictionless experience that boosts completion rates.
- White-Label Solution: Fully brand the signing UI to match your application.
- Higher Conversion: Reduce user drop-off by eliminating redirects to external sites.
- Full Control: Manage the entire user journey via the API, from document creation to post-signature redirects.
const { signUrl } = await eSignly.signatures.createEmbedded({
documentId: 'doc_123',
signer: { email: '[email protected]' },
redirectUrl: 'https://yourapp.com/success'
});
// Render signUrl in an iframeAutomate Repetitive Documents
Create reusable templates for your most common documents like NDAs, sales contracts, or offer letters. Pre-define signer roles and form fields, then populate them dynamically via the API for ultimate efficiency.
- Drastic Time Savings: Eliminate the need to manually prepare each document.
- Consistency & Accuracy: Ensure all documents are standardized and error-free.
- Dynamic Data Population: Use API calls to merge customer data directly into template fields.
await eSignly.signatures.createFromTemplate({
templateId: 'tmpl_nda_456',
signers: [
{ role: 'Client', email: '[email protected]' },
{ role: 'Internal', email: '[email protected]' }
],
mergeFields: { client_name: 'Acme Corp' }
});Real-Time Status Updates
Stay in sync with every step of the signing process. Our webhooks send real-time notifications to your server for key events like 'document viewed', 'signed', or 'completed', allowing you to trigger downstream actions automatically.
- Automate Workflows: Automatically update your CRM or provision an account once a contract is signed.
- Instant Notifications: Get immediate feedback without constantly polling the API.
- Reliable & Secure: Events are signed to ensure authenticity and integrity.
{
"event": "signature_completed",
"data": {
"document_id": "doc_123",
"signer_email": "[email protected]",
"signed_at": "2026-01-14T14:30:00Z"
}
}Use the REST API with Your Preferred Language
Connect from Node.js, Python, Ruby, Java, .NET, Go or another language using standard HTTPS requests. An SDK is not required. Start with the current documentation for authentication, endpoints and request parameters; the workflow snippets on this page are illustrative.
Read API Authentication and Request Examples
See How Businesses Build with eSignly
From fast-growing startups to established enterprises, companies rely on our API to power their core business processes.
ScaleUp SaaS Inc.
Client Overview: SiteZeus is a leading SaaS platform providing location intelligence solutions. They needed to streamline their customer onboarding process, which involved manual contract generation and signing, causing delays and user drop-off.
"The eSignly API was a game-changer. We automated our entire contract workflow in a weekend, and the impact on our sales cycle was immediate." - Ava Harrington, VP of Engineering
Key Challenges:
- Manual, time-consuming contract process.
- High friction in the final stage of customer acquisition.
- Lack of visibility into contract status.
- Scalability concerns with their manual process.
Our Solution:
We worked with SiteZeus to integrate the eSignly API directly into their signup flow. Using our embedded signing and template features, they automated the entire process:
- A template was created for their standard Master Service Agreement.
- When a new customer signs up, the API dynamically populates the template with their details.
- The signing process is embedded directly in their dashboard for a seamless experience.
- Webhooks notify their system instantly upon completion, triggering account activation.
InnovateRealty Tech
Client Overview: InnovateRealty provides a property management platform for large residential portfolios. They needed a robust, scalable, and legally compliant way to handle thousands of lease agreements each month across multiple states.
"Reliability and legal compliance are non-negotiable for us. eSignly's API delivers on both, with detailed audit trails that give us and our clients complete peace of mind." - Michael Brooks, CTO
Key Challenges:
- Handling high volumes of sensitive legal documents.
- Ensuring compliance with state-specific real estate laws.
- Providing a simple, mobile-friendly signing experience for tenants.
- Securely storing and retrieving executed agreements.
Our Solution:
InnovateRealty leveraged the eSignly API to build a fully automated leasing workflow:
- Utilized API-driven templates for different property types and states.
- Integrated bulk sending capabilities to manage lease renewals for entire buildings at once.
- Implemented a secure, responsive signing flow accessible on any device.
- Used the API to automatically archive completed documents with their comprehensive audit trails into their system.
EnterpriseHR Solutions
Client Overview: EnterpriseHR is a global human resources software provider for large corporations. Their platform needed a secure and efficient way to manage the entire employee lifecycle documentation, from offer letters to policy acknowledgments.
"The security features and detailed audit trails of the eSignly API were critical for our enterprise clients. The integration was smooth, and their support team was fantastic." - Jenna Raynor, Product Manager
Key Challenges:
- Meeting the stringent security requirements of enterprise clients.
- Managing complex workflows with multiple internal approvers.
- Ensuring a positive, professional experience for new candidates.
- Creating a verifiable, tamper-proof record of all signed documents.
Our Solution:
EnterpriseHR integrated the eSignly API to power their document management module:
- Set up sequential signing workflows for offer letters requiring manager and HR approval.
- Used templates to standardize onboarding packages for different roles and locations.
- Leveraged the API to provide real-time status tracking within their HR dashboard.
- Relied on the detailed audit trail for each document to ensure full compliance and legal defensibility.
Trusted by Developers Who Build
"The eSignly API documentation is one of the clearest I've ever worked with. We went from kickoff to production integration in a single sprint. It just works."
"Scalability was our biggest concern. The eSignly API handles our peak leasing season volume without a hiccup. Their infrastructure is rock-solid."
"The embedded signing feature was a must-have for us. The ability to completely white-label the experience kept our users engaged and our brand front-and-center."
Enterprise-Grade Security & Compliance
We're certified to meet the highest global standards for security, privacy, and legal validity, so you can build with confidence.
SOC 2 Type II
ISO 27001
PCI DSS
HIPAA Compliant
GDPR Compliant
Simple Pricing That Scales With You
Review current API plans, testing access and production requirements before choosing an integration path.
Review Current API Plans
Confirm usage limits, billing terms, available features and support for your intended workflow. Contact the team about volume or enterprise requirements.
View Full API PricingFrequently Asked Questions
Are eSignatures sent via the API legally binding?
Electronic signatures may have legal effect under applicable laws, including the U.S. ESIGN Act and UETA. Requirements vary by document, jurisdiction and workflow. Audit-trail evidence can support review; confirm the requirements for your intended use.
How does API pricing work?
Review the API pricing page for current plans, usage limits and billing terms. Testing access and production access can depend on the account and plan; confirm the requirements before integrating.
What kind of support do you offer for developers?
Start with the API documentation and available examples. Contact the team to confirm support channels, onboarding assistance and any plan-specific terms for your integration.
Can I customize the look and feel of the signing page?
Embedded-signing and branding options depend on your API plan and configuration. Review the API documentation and confirm supported customization, embedding and redirect behavior for your intended workflow.
How do you ensure the security of documents and data?
eSignly is SOC 2 Type II and ISO 27001 certified. Review the security information and applicable report scope. Confirm data handling, access controls and contractual requirements for your intended workflow.
Ready to Build with eSignly?
Review API plans and documentation, then contact the team about access or integration requirements.
View API Plans