Add text on a PDF document for eSignature with C# Client using the API

Instantly type and insert text anywhere on a PDF document using the signNow API. Place text fields, adjust their size and insert any information that needs to be shared with other users.

☝️ Need a test drive?
  • Free to test
  • Fast to deploy
  • Powerful & secure

Share your comments and easily complement information on a PDF for recipients with added text.

Make discussions and understanding information in any document smooth and simple.

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  • We provide developers with complete SDKs for all popular languages, allowing them to integrate eSignature workflows without writing a single line of code.
  • With our detailed documentation, integrating the signNow API is a breeze.
  • The signNow API not only provides you with eSignatures: use it to create fillable forms, request payments, and download & archive documents using simple API calls.

signNow regularly wins awards for ease of use and setup

Read our reviews on the trusted resources

Tech Data uses signNow to improve our internal and external customer service while increasing our speed to revenue.
Bob Dutkowsky CEO
Bob Dutkowsky | CEO

Select an API package for your business

Integrate eSignatures into your software and get 250 legally-binding signature invites with your API free trial.

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Solution engineers

We are here to help you configure eSignature API to your workflow.

Review signNow’s API documentation

The detailed API tutorial will guide you through the entire integration process and provide clear coding examples.

Video guides

Watch our video guides for instructions on how to easily build custom integrations.

Start with any of our SDKs

Get complete SDKs for Node.js, Python,
PHP, Java, C#.

Enterprise-grade security and compliance

signNow is committed to protecting your sensitive information by complying with global industry-specific security standards.

GDPR compliance
GDPR compliance
Regulates the use and holding of personal data belonging to EU residents.
SOC 2 Type II Certified
SOC 2 Type II Certified
Guarantees the security of your data & the privacy of your clients.
PCI DSS certification
PCI DSS certification
Safeguards credit/debit card data for every monetary transaction a customer makes.
21 CFR Part 11
21 CFR Part 11
FDA-backed standards for electronic documentation and electronic signatures.
HIPAA compliance
HIPAA compliance
Protects the private health information of your patients.
CCPA compliance
CCPA compliance
Enhances the protection of personal data and the privacy of California residents.

Watch the signNow API in action

Get started with uninterrupted eSignature API: add text on a PDF document for eSignature with C# Client using the API

Consolidate and streamline your eSignature workflows and establish seamless processes. Try the signNow API, implement eSignature workflows into your custom apps and websites in minutes, and seamlessly add text on a PDF document for eSignature with C# Client using the API.

Add text on a PDF document for eSignature with C# Client using the API the signNow API for uninterrupted eSignature API

  1. Click API on the signNow main page and create your API Sandbox account.
  2. Open your email to confirm the registration and specify a password for accessing your Developer Sandbox environment.
  3. Find the list of your apps at the top of the page. By default, you can also find a Test App for testing the API.
  4. Click its name to access the Client ID and Basic Authorization Token.
  5. Launch the API using the information from the previous step.
  6. Use the code samples from the signNow library.
  7. When you're ready to go live, go to your signNow account and choose a subscription plan.
  8. If you can't find a subscription that suits your needs, contact the Sales team.
  9. Change the test URL in your requests to the production environment URL.
  10. Delight your customers and partners with a streamlined eSignature experience.

The signNow API is straightforward to embed, test, and operate (no sales people engaged). Gain the opportunity to add text on a PDF document for eSignature with C# Client using the API conveniently. Choose signNow to get more optimized eSignature workflows.

How it works

Create an account and access the API Dashboard
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Track how your productivity grows with accelerated workflows

Watch our instructions to build custom integrations with ease

signNow offers a free testing environment to explore the eSignature.

Trusted eSignature solution — what our customers are saying

Explore how the signNow eSignature platform helps businesses succeed. Hear from real users and what they like most about electronic signing.

Great Way To Get Documents Signes
5
Joyce Paul

What do you like best?

I’ve been using SignNow for the last four years. It’s a great way to get documents signed while also protecting documents. It’s easy to use and user friendly for those you request for their signatures. I would recommend all businesses to use this. It’s easier than some of the other products that are out there now. I am always getting transcripts request or need signatures for attendance records, report cards, etc.

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Affordable and easy to use
5
Consultant in Health, Wellness and Fitness

What do you like best?

Templates you can customize so when you send similar forms to new people it's all ready to go and you just have to change their name. Very reasonable prices.

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Makes job efficient and easier!
5
Administrator in E-Learning

What do you like best?

I really like how SignNow makes job easier mostly during this pandemic. We use SignNow in our business to communicate with clients and it makes it easier without having a direct contact and clients can just sign them at their time. I also like how SignNow is very detailed and easy to access.

Read full review

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FAQs

Below is a list of the most common signNow API questions and answers. Just choose a question to view a detailed answer.

Need help? Contact support

Ready to get started?

It’s time to watch the signNow API in action. Create your developer account and upload documents, request signatures, and check the status of your document.

Why choose the signNow API?:

  • Free to test and easy to deploy
  • SDKs for popular languages
  • Customizable for any workflow
  • Industry-leading security & compliance