What is the Embedded Signing API?

The Embedded Signing API allows you to embed Blueink's secure signing experience directly into your application or website. It lets users complete document signing without leaving your platform, providing a seamless, on-brand experience while maintaining full compliance and security.

How does embedded signing differ from standard signing links?

Unlike standard signing links that redirect signers to a Blueink-hosted page, embedded signing keeps the process within your own interface. This improves user experience, reduces drop-offs, and provides more control over the signing flow.

Is embedded signing secure and legally binding?

Yes. All embedded signing sessions follow the same security, encryption, and compliance standards as any Blueink transaction. Every signature is backed by a detailed Certificate of Evidence and complies with ESIGN, UETA, GDPR, and other eSignature compliance requirements.

What authentication options are available for embedded signers?

You can use standard email-based authentication or add extra security layers like SMS verification or ID capture. These options help confirm signer identity before the embedded signing session begins.

Can I track or receive updates for embedded signing events?

Yes. You can use Blueink's webhooks to receive real-time updates when key events occur during an embedded signing session, including when a signer opens or completes signing, and when completed documents are ready for download. In addition, the embedded signing iframe emits events to the parent browser window, so that your App can react accordingly to create seamless signing experiences.

Embed Envelope Preparation Into Your App Without a
PDF SDK

Blueink's embedded envelope preparation API opens a secure preparation session in your product. Users upload PDFs or choose templates, add signers, and place signature fields without leaving your platform. No PDF SDK required.

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Embedded Envelope Preparation with the Blueink
eSignature API

Skip building your own PDF editor. Create a preparation session with one API call, load the returned URL in an iframe, and let users set up documents for signature in your own interface.

Upload PDFs or start from your templates

Let users upload their own PDFs or start from the document templates you approve. You can limit the template list to specific templates or folders, so users only see the documents that apply to them.

Blueink Embedded Envelope Preparation API showing options to upload PDFs or select approved templates for eSignature.

Blueink Embedded Envelope Preparation API showing signer assignment and eSignature field placement inside an embedded app.

Add signers and place fields

Users add one or more signers, place signature and form fields directly on the document, and submit it when it's ready. The whole setup happens inside your app, without a separate eSignature dashboard.

Save drafts and resume later

Pass an existing draft to reopen a preparation session exactly where the user left off.

Blueink Embedded Envelope Preparation API showing how to reopen saved envelope drafts and resume eSignature preparation.

Why in-app envelope preparation matters

No More Switching Between Apps

Let users prepare and send envelopes directly inside your app without interrupting their workflow.

Skip building a PDF editor

Field placement, signer setup, and validation take months to build with a PDF SDK.

Keep the experience in your product

Users prepare documents in your app instead of a separate eSignature dashboard.

Keep track of every draft

Drafts stay tied to your app, so users can pick up where they left off.

Start preparing envelopes in minutes

Create an embedded envelope preparation session with one API call, then load the returned URL in your app.

terminal

# Create an embedded envelope preparation session

curl -X POST "https://api.blueink.com/api/v2/bundles/preparation_session/" \

-H "Authorization: Token YOUR_API_KEY" \

-H "Content-Type: application/json" \

-d '{ "upload_pdf": true }'

# 201 Created → load "url" in an iframe before "expires"

create_session.py

import os

import requests

resp = requests.post(

"https://api.blueink.com/api/v2/bundles/preparation_session/",

headers={"Authorization": f"Token {os.environ['BLUEINK_PRIVATE_API_KEY']}"},

json={"upload_pdf": True},

)

session = resp.json() # contains "url" and "expires"

createSession.js

const res = await fetch("https://api.blueink.com/api/v2/bundles/preparation_session/", {

method: "POST",

headers: {

Authorization: `Token ${process.env.BLUEINK_PRIVATE_API_KEY}`,

"Content-Type": "application/json",

body: JSON.stringify({ upload_pdf: true }),

});

const session = await res.json(); // { url, expires }

create_session.php

$ch = curl_init("https://api.blueink.com/api/v2/bundles/preparation_session/");

curl_setopt_array($ch, [

CURLOPT_POST => true,

CURLOPT_RETURNTRANSFER => true,

CURLOPT_HTTPHEADER => [

"Authorization: Token " . getenv("BLUEINK_PRIVATE_API_KEY"),

"Content-Type: application/json",

CURLOPT_POSTFIELDS => json_encode(["upload_pdf" => true]),

]);

$session = json_decode(curl_exec($ch), true); // url, expires

CreateSession.cs

using System.Net.Http.Json;

using System.Text.Json;

var apiKey = Environment.GetEnvironmentVariable("BLUEINK_PRIVATE_API_KEY");

using var http = new HttpClient();

http.DefaultRequestHeaders.Add("Authorization", $"Token {apiKey}");

var res = await http.PostAsJsonAsync(

"https://api.blueink.com/api/v2/bundles/preparation_session/",

new { upload_pdf = true });

var session = await res.Content.ReadFromJsonAsync<JsonElement>(); // url, expires

View Developer Docs

Smart Pricing for Every Business Size

Pay for what you actually need, with lower per-envelope rates as your usage expands.

Volume Discounts

API Envelopes

$0.95

Per Envelope

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Total: $950

What’s Included

Volume Discounts

Save up to 75% with larger purchase

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Unlimited testing during development

Up to 5 users

Multi-user access for your team

Developer dashboard

Comprehensive analytics and monitoring

Select Credit Amount: 1,000 credits

API Envelopes

Price per Envelope

Discount

Up to 1,000

$0.95

Scale pricing as you grow

5,000

$0.75

Save 21%

25,000

$0.60

Save 37%

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Save 53%

250,000

$0.35

Save 63%

500,000

$0.28

Save 71%

1,000,000

Best Value

$0.24

Save 75%

Up to 1,000

Scale pricing as you grow

$0.95

per envelope

5,000 Envelopes

Save 21%

$0.75

per envelope

25,000 Envelopes

Save 37%

$0.60

per envelope

100,000 Envelopes

Save 53%

$0.45

per envelope

250,000 Envelopes

Save 63%

$0.35

per envelope

500,000 Envelopes

Save 71%

$0.28

per envelope

1,000,000 Envelopes

Best Value

Save 75%

$0.24

per envelope

Create Your Free API Account

Manage and purchase credits once your account is created.

FAQs

What is embedded envelope preparation?

Embedded envelope preparation lets your users prepare and send documents for eSignature in an embedded experience in your app. They upload a document or choose a template, add signers, and place fields in a secure session that Blueink hosts in an iframe.

How is embedded envelope preparation different from embedded signing?

Embedded envelope preparation is for the sender, who sets up the envelope. Embedded signing is for the signer, who reviews and signs it. Many apps use both.

What is a signature field?

A signature field marks where a specific signer needs to sign. You can also add initials, date, text, checkbox and any other fields supported by Blueink.

Do I need a PDF SDK to add envelope preparation to my app?

No. Blueink hosts the full preparation experience in the iframe, including document viewing and field placement. Your app only needs to create a session through the Blueink API and load the link it returns.

Which documents can users work with?

Users can upload their own documents in PDF, Word or other Office formats, or pick from their Blueink templates. When creating the embedded preparation session, you decide which templates or template folders they can see, and you can reopen a saved draft so they can finish it.

How do I know when the embedded envelope preparation session is finished?

The embedded iFrame emits events to the parent window, so your app can react accordingly to create a seamless user experience. In addition, Blueink can send webhooks to notify your app when the Envelope is sent, completed, or when other events occur in the Envelope lifecycle.

Do my users need a Blueink account?

No. You as an App developer need a Blueink account to connect to the Blueink API, but your users prepare and send envelopes inside your app without their own Blueink login. Signers don't need an account either.

Can I match the preparation screen to my brand?

You can customize the color and text of the Send button in the preparation session. With Signing Brands, you can add your logo and company name, and customize colors and messaging through other parts of the signing experience.

Embed Envelope Preparation Into Your App Without a PDF SDK

Embedded Envelope Preparation with the Blueink eSignature API

Upload PDFs or start from your templates

Add signers and place fields

Save drafts and resume later

Why in-app envelope preparation matters

No More Switching Between Apps

Skip building a PDF editor

Keep the experience in your product

Keep track of every draft

Start preparing envelopes in minutes

Smart Pricing for Every Business Size

Volume Discounts

API Envelopes

$0.95

53% DISCOUNT

What’s Included

Volume Discounts

No Expiration

Free to Test

Up to 5 users

Developer dashboard

Select Credit Amount: 1,000 credits

API Envelopes

Price per Envelope

Discount

Up to 1,000

$0.95

Scale pricing as you grow

5,000

$0.75

Save 21%

25,000

$0.60

Save 37%

100,000

$0.45

Save 53%

250,000

$0.35

Save 63%

500,000

$0.28

Save 71%

1,000,000

Best Value

$0.24

Save 75%

Up to 1,000

Scale pricing as you grow

$0.95

per envelope

5,000 Envelopes

Save 21%

$0.75

per envelope

25,000 Envelopes

Save 37%

$0.60

per envelope

100,000 Envelopes

Save 53%

$0.45

per envelope

250,000 Envelopes

Save 63%

$0.35

per envelope

500,000 Envelopes

Save 71%

$0.28

per envelope

1,000,000 Envelopes

Best Value

Save 75%

$0.24

per envelope

Bronze

Silver

Gold

Embed Envelope Preparation Into Your App Without a
PDF SDK

Embedded Envelope Preparation with the Blueink
eSignature API