Powerful eSignature API
built for developers
Easily embed end-to-end eSignature workflows into your apps. Trusted by millions,
our 24+ years of API expertise ensures an excellent user experience.
Postman Developer Choice Award - 2025
Recognized by developers worldwide for ease of integration.
Trusted by 50,000+ businesses worldwide
- Fast and reliable
Start sending contracts in minutes
Deliver seamless eSignature experiences with just a few lines of code.
# Replace with the template ID from your BoldSign web application.
curl -X 'POST' \
'https://api.boldsign.com/v1/template/send?templateId={your_template_id}' \
-H 'accept: application/json' \
-H 'X-API-KEY: {your_api_key}' \
-H 'Content-Type: application/json' \
-d '{
"roles": [
{
"roleIndex": 1,
"signerName": "David",
"signerEmail": "david@cubeflakes.com"
}
]
}'
using BoldSign.Api;
var apiClient = new ApiClient { ApiKey = "your_api_key" };
var templateClient = new TemplateClient(apiClient);
// Replace with the template ID from your BoldSign web application.
var documentCreated = templateClient.SendUsingTemplate(new()
{
TemplateId = "your_template_id",
Roles =
[
new()
{
RoleIndex = 1,
SignerName = "David",
SignerEmail = "david@cubeflakes.com"
}
]
});
ApiClient apiClient = Configuration.getDefaultApiClient();
apiClient.setApiKey("your_api_key");
TemplateApi templateApi = new TemplateApi(apiClient);
Role role = new Role();
role.setRoleIndex(1);
role.setSignerName("David");
role.setSignerEmail("david@cubeflakes.com");
// Replace with the template ID from your BoldSign web application.
String templateId = "your_template_id"
SendForSignFromTemplateForm sendForSign = new SendForSignFromTemplateForm();
sendForSign.setRoles(Arrays.asList(role));
DocumentCreated documentCreated = templateApi.sendUsingTemplate(templateId, sendForSign);
<?php require_once "vendor/autoload.php";
$config = new BoldSign\Configuration();
$config->setApiKey('your_api_key');
$template_api = new BoldSign\Api\TemplateApi($config);
$roles = new BoldSign\Model\Role();
$roles->setRoleIndex(1);
$roles->setSignerName("David");
$roles->setSignerEmail("david@cubeflakes.com");
// Replace with the template ID from your BoldSign web application.
$template_id= "your_template_id";
$send_for_sign = new BoldSign\Model\SendForSignFromTemplateForm();
$send_for_sign->setRoles([$roles]);
$document_created = $template_api->sendUsingTemplate($template_id, $send_for_sign);
import boldsign
configuration = boldsign.Configuration(api_key="your_api_key")
with boldsign.ApiClient(configuration) as api_client:
template_api = boldsign.TemplateApi(api_client)
role = boldsign.Role(
roleIndex=1,
signerName="David",
signerEmail="david@cubeflakes.com"
)
# Replace with the template ID from your BoldSign web application.
template_id = "your_template_id"
send_for_sign = boldsign.SendForSignFromTemplateForm(
roles=[role]
)
document_created = template_api.send_using_template(template_id, send_for_sign)
import { TemplateApi } from 'boldsign';
import { Role, SendForSignFromTemplateForm } from 'boldsign';
const templateApi = new TemplateApi();
templateApi.setApiKey('your_api_key');
const role = new Role();
role.roleIndex = 1;
role.signerName = "David";
role.signerEmail = "david@cubeflakes.com";
// Replace with the template ID from your BoldSign web application.
const templateId = "your_template_id";
const sendForSign = new SendForSignFromTemplateForm();
sendForSign.roles = [role];
const documentCreated = templateApi.sendUsingTemplate(templateId, sendForSign);
- Key stats
Why BoldSign?
Years in business
Countries
Customers
Uptime reliability
- Key features
Powerful features, designed for developers
Custom Signing Experience
Show your logo and colors on signing pages to build trust with a consistent look.
Embed Signing within Your App
Send requests and let signers complete documents inside your app for smoother flows.
Secure Signer Verification
Validate signer IDs to protect sensitive deals, prevent fraud, and ensure compliance.
Scale Across SaaS Clients
Give each client its own signing setup with multitenant scale and custom branding.
Real-Time Document Updates
Get instant notifications for signing events and trigger workflows with no manual work.
Simplify Document Preparation
Use text tags to auto-map signer fields, saving time and cutting down on document errors.
- API dashboard
Developer-friendly dashboard and tools
Track and manage your eSignature processes using our centralized API dashboard with real-time insights, detailed reports, and a dedicated sandbox environment.
Real-Time Insights
Monitor API usage and performance metrics in real time
Detailed Reports
Gain full visibility into document tracking and API activity logs.
Sandbox Environment
Test and refine your integration before going live.
- SDKs
BoldSign SDKs: A developer’s best friend
BoldSign provides SDKs for leading frameworks, ensuring effortless integration into your existing tech stack — no matter what it looks like.
Security And Compliance
Legally Valid.
Fully Secure.
Always Compliant.
BoldSign meets top global standards like SOC 2, GDPR, HIPAA, and PCI DSS. Every signature is legally enforceable under the ESIGN Act, eIDAS, and global laws. With AES-256 encryption, your data stays protected from start to finish.
- Scalability
Built for scale and performance
Whether you’re sending 10 or a million documents, BoldSign is engineered to scale with your business. Experience lightning-fast signing speeds and reliable API responses, even with heavy traffic.
Enterprise
Starts at $30/mo, includes 40 envelopes
- Customized branding
- Embedded requesting
- Embedded signing
- Embedded templates
- Embedded custom field
- Unlimited templates
- ID verification
Reviews
Don't take our word for it.
Check out our reviews on G2 to see what customers have to say about BoldSign.
Great and Simple product
I was looking for a simple and easy to use system that was not going to break the bank. Bold Sign delivers in all aspects. Easy to use and outstanding cost structure.
Abraham M.
Posted on April 28, 2025
Great experience with BoldSign
BoldSign streamlines our document signing process. Its intuitive design and reliable customer service make it a pleasure to use. The software is very user friendly.
Kevin R.
Posted on March 11, 2025
Very satisfied with BoldSign
BoldSign is easy to use and has been a seamless integration into our workflow. Very user friendly and easy to navigate. Customer service is helpful and responsive.
Cassie S.
Posted on March 25, 2025
- Best in-class documentation
Quick Start: Integrate BoldSign
APIs Effortlessly
Interactive Use Case Demo
Experience how BoldSign fits into real-world scenarios with our interactive demos. Explore key workflows and see the API in action.
Postman Collection
Quickly test and explore our API with the preconfigured Postman collection. Save time with ready-to-use API calls and examples.
API Reference
Access comprehensive API documentation with detailed endpoints and request/response examples for seamless integration.
API Explorer
Interact with the BoldSign API in your browser. Test requests, view responses, and get instant feedback in real time.
SDKs
Simplify integration with our SDKs for popular programming languages like .NET, Python, Node.js, and more.
- FAQs
Frequently Asked Questions
The eSignature API empowers developers to seamlessly integrate the entire electronic signature functionality into their own applications, and enables users to electronically sign, send, track, and manage documents.
You can perform a wide range of eSignature functionalities, including creating signature requests, tracking document status, downloading signed documents and audit trails, managing templates, customizing branding, and much more.
The cost of the eSignature API depends on the number of documents you send out for signature, with a cost of $0.75 per document. Check out our pricing page for more information.
Yes. With BoldSign, you can send signature requests on behalf of other users. To do this, simply add the intended user as the sender identity, but you will need to get their approval before proceeding.
Yes, you can explore API’s capabilities and test the integration without any cost by signing up to the free developer sandbox account.
Yes — BoldSign’s REST API uses TLS in transit, strong authentication and complies with UETA, eIDAS, E‑SIGN Act, SOC 2 Type II, HIPAA, GDPR, and PCI DSS for secure, legally valid e‑signatures.
There is no direct API for bulk sending. However, you can send documents to multiple recipients using templates and looped API calls—ideal for HR onboarding, policy acknowledgments, and mass agreements. you can use this.
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