Developer Documentation
Integrate document signing, forms, cases, and webhooks with NextSign.
Browse the official API reference for authentication, form submission, case lifecycle management, document retrieval, and event-driven integrations.
Authorization
Find your API key, bearer token flow, and the companyId used in requests.
Forms
Fetch templates, inspect tags, and submit forms to generate new signing cases.
Cases
Create, retrieve, list, and manage signing cases across your integration.
Documents
Retrieve signed files and convert source documents before they are sent.
Webhooks
Subscribe to case and flow events with verified trigger and retry behavior.
Test Environment
Build against a separate test account without affecting production data.
Partner Program
Offer e-signing that looks like your own.
Co-branded signup
Customers sign up through your referral link on a page with your name and logo.
Full white-labelling
Signing pages, links and emails on your own domain, with your logo and design.
Discount and kickback
Referred customers get a discount on credits, and you earn a share of what they spend.
API key by webhook
Receive a ready-to-use API key for every new account, with the customer’s consent.
POST your-endpoint · New referred customer
{
"trigger": "partner.customer.registered",
"company": {
"id": "66263484e601d81006d1a132",
"name": "Sample Customer ApS",
"cvr": "12345678",
"apiKey": "key_Wb22OsfMPpEkAHeS6LHq..."
}
}