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OnTask’s eSignature API: Enhance Your Application
An eSignature API built to fill the gaps in your application in minutes and get to market faster.


An Electronic Signature API Your Way
Building secure, compliant, and legally binding eSignature capabilities into your software takes up valuable time and development resources.
Get that time back and avoid development headaches with a secure, proven API solution backed by the support, documentation, and resources of a software company with three decades of experience.
Pay-as-you-go Pricing Per eSign
1-1000 transactions / month
$1.87 per transaction
1001-5000 transactions / month
$1.74 per transaction
5000+ transactions / month
$1.49 per transaction
Discount and user-based pricing available.
Advanced features such as custom workflows, custom SMTP, white labeling, embedding, and SMS are available.
Get Started with Developer Resources


View our documentation to learn more about OnTask API and its capabilities.


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I think the combination of all that they bring to the table in a mature capacity is the reason to do business with them. They didn’t just invent something yesterday and hope it’s working. They have tried and true platforms and people who understand the business and how to make things work.
CEO of HubSync




The Benefits of Buying vs. Building an eSign API
To build or to buy can be a hard question to answer. See how the benefits stack up in our latest eSign API-focused whitepaper.




Bring eSignatures Full Circle with Robust Workflows
Legally Binding eSignatures
Collect legally binding, HIPAA-compliant eSignatures from any device.
Progress Tracking
Track signature status as documents flow through review.
Collect, Populate, & Generate Documents
Use digital forms to collect info from users to populate pre existing documents or generate new ones.
Built-In Notifications
Automatically route documents to proper parties using emails and SMS texts.
Quick Integrations
Easily connect with thousands of apps using webhooks and in-app integrations.
Reusable Templates
Quickly automate processes by getting started with a pre-built template.
Why Choose OnTask API?
OnTask API connects eSignatures with forms and workflows to bring you an end-to-end solution for automating processes.
- 30+ Years in the Business
- Scales with Your Team
- Proven Reliability
- Quick Error Response
- Transparent Pricing
- Robust Documentation
OnTask API Business Benefits
Seamless User Experience
Integrate forms and signature features directly into applications to create a consistent user experience.
Unrivaled Support
Extensive documentation and proactive customer support help to overcome any implementation challenges.
Get to Market Faster
Save time and resources by incorporating proven functionality into applications rather than building from scratch.
Secure and Compliant
HIPAA, FERPA, SOC2, & CCPA compliant with legally binding signatures and electronic audit trails for enhanced security.
Get Started in Minutes
Integrate versatile forms, documents, and signature capabilities and start creating API calls in a matter of minutes.
Do More with Our eSignature API
Signatures
Add secure, compliant, legally binding signature functionality into your native forms and applications.
Forms
Embed dynamic digital forms into your applications or website for easy, simplified data collection.
Documents
Find and replace document fields, generate documents from form data, and bulk send documents.
Workflows
Automatically route forms and documents to the proper parties for signature, review, and completion.
Built for Developers
Fast API Error Response
Consistent infrastructure monitoring with automatic reminders notify our team to minimize downtime and errors.
Clear Documentation
Concise, straightforward documentation for using and integrating OnTask API into applications.
Built to Last
OnTask API is flexible to changing needs with easy editing and scalability as your business grows.
Maintains Backward Compatibility
As updates are made, backward compatibility is maintained to ensure continuous functionality.
Frequently Asked Questions
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What compliances does the OnTask eSign API meet?
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OnTask API is HIPAA, FERPA, SOC 2, and CCPA compliant, and features a number of security features to protect data and combat downtime. Read about OnTask’s security and compliance.
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What use cases does the API support?
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OnTask API can be used for a wide variety of use cases, including but not limited to leasing packets, employee and client onboarding, proposals, quotes, questionnaires, and any other process using forms and documents.
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What capabilities does the API have?
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OnTask API’s abilities include eSignature requests and collection on documents, document packet creation, automated document generation, document lifecycle management and storage, data collection through forms, automatic launching of workflows, as well as importing and exporting documents and data from other systems.
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How long does it take to launch the API?
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Our eSignature API comes with extensive documentation that allows developers to implement and launch within a matter of minutes. Support is available during and after implementation, as well as
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eSignature vs. digital signature API, what’s the difference?
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The purpose of an eSignature is to verify a document, while digital signatures also work to secure documents. OnTask utilizes both for a complete signature experience. Read more on the difference between eSignature and digital signature APIs.
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What is an eSignature API?
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An eSignature (electronic signature or digital signature) application programming interface (API) is a Representational State Transfer (REST) web service that allows subscribers to securely request signatures online, obtain status updates, and download the completed documents.
Request Your Custom API Solution
Every business has different needs, but we’re here to help. Tell us a little more about what you’re looking for, and we’ll advise you on the best solution for you.