eSignature API for Modern Developers
Build seamless, secure, and compliant document signing workflows directly into your application. Get your first API call running in under 5 minutes.
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.
Guaranteed Uptime & Reliability
Build on a platform you can trust. We offer up to a 100% uptime SLA, ensuring your critical document workflows are always operational, no matter the scale.
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
No hidden fees or complex contracts. Our straightforward, volume-based pricing scales with your business, with a generous free tier for development and testing.
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.
Go Live in 3 Simple Steps
Integrate our eSignature API and send your first document in minutes, not weeks. Here’s how easy it is to get started.
Get Your API Key
Sign up for a free developer account to get instant access to your sandbox and production API keys.
Install an SDK
Use our official libraries for your favorite language to simplify authentication and API calls.
npm install @esignly/node-sdkSend Your First Request
Use a few lines of code to upload a document and send your first signature request.
const eSignly = require('@esignly/node-sdk');
eSignly.configure({ apiKey: 'YOUR_API_KEY' });
// ... send documentPowerful API Features & Use Cases
Discover how our flexible API can power your most critical business workflows, from customer onboarding to internal approvals.
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: 'customer@example.com' },
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: 'client@corp.com' },
{ role: 'Internal', email: 'legal@esignly.com' }
],
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": "customer@example.com",
"signed_at": "2026-01-14T14:30:00Z"
}
}SDKs & Libraries for Your Stack
We provide robust, well-documented SDKs to make integration with your existing technology stack as simple as possible.
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
21 CFR Part 11
Simple Pricing That Scales With You
Start for free in our developer sandbox. Upgrade to a production plan when you're ready to go live. No surprises, just clear, value-based pricing.
API Plans Start At $60/month
Our plans include a generous number of API calls, with volume discounts available for enterprise needs. All plans include access to our full feature set and developer support.
View Full API PricingFrequently Asked Questions
Yes. eSignly signatures comply with the U.S. ESIGN Act, UETA, and other international laws. Every signed document comes with a comprehensive, court-admissible audit trail that tracks every action taken on the document, ensuring legal validity.
Our API plans are based on the number of signature requests you send per month. We offer several tiers to fit different volumes, from startups to large enterprises. All plans include a free sandbox for unlimited testing. You can find detailed information on our API pricing page.
We offer comprehensive support for all developers. This includes detailed API documentation, code examples, and SDKs. All paid plans come with email support from our technical team. Enterprise plans include options for a dedicated Slack channel and onboarding assistance.
Absolutely. Our embedded signing feature allows you to fully white-label the signing experience. You can control the branding, colors, and post-signing redirects to create a seamless flow that keeps users within your application's environment.
Security is our top priority. All data is encrypted in transit and at rest using AES-256 bit encryption. Our platform is hosted in SOC 2 Type II certified data centers, and we adhere to strict security protocols and regular third-party audits to ensure your data is always protected.
Ready to Build with eSignly?
Create your free developer account and get your API keys in seconds. Start building powerful, automated document workflows today.
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