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Looking for an alternative to WebMerge API?

Learn how PandaDoc API can be easily customized and integrated beyond our out-of-the-box solution.

Looking for an alternative to WebMerge API?
WebMerge APIPandaDoc
Embedded Signing and Sending
Templates Unlimited Unlimited
Basic Fields
Sandbox API Test mode


API – short for Application Programming Interface – give developers a set of coding instructions that can expedite the customization and integration of apps such as the merging of document data into applications. In the case of WebMerge ( and PandaDoc, the API lets you build on the basic functionality of the two solutions and to optimize their utility within your organization. Both companies offer REST APIs, which represent state of the art technology for this kind of coding interface, but the PandaDoc API offers considerably more fine-tuned functionality to customize and personalize your document workflow.

Customizable branding

Both companies allow you to customize your documents to include elements like logos, images, corporate colors, and fonts so that you can stay on-brand. The PandaDoc API provides a significantly richer set of controls than WebMerge so if branding is important for your organization, you’ll want to take this into account.

Embedded sign and send

Typically companies offer the ability to embed electronic signatures within third-party applications, and the PandaDoc API functionality is far superior to that of WebMerge API. The REST interface allows developers to embed robust paperless eSignatures and sending functionality into existing workflows and software like CRM and other sales and marketing software tools.

Unlimited templates

PandaDoc and WebMerge distinguish themselves by providing an unlimited number of templates for expediting form and document creation. That means you don’t need to start from scratch when you want to create a new doc: you can simply modify an existing template. However, at the API level, PandaDoc allows templates to be edited programmatically on the server side rather than being modified on a one-off basis by end-users.

Flexibility to scale faster

Security protocols

WebMerge and PandaDoc employ an industry standard OAuth 2.0 for authenticating docs as well as 256-bit SSL security and to safely keep your transmitted data. Both use API Key and Secret combinations, letting users create their own API Key and use multiple API Keys within their accounts. Both store data on the robust AWS server.


Customizable data fields

Relative to the WebMerge API, PandaDoc API makes it easier to customize commonly-used documents such as proposals, quotes, and contracts. This way you can aggregate data more efficiently without performing redundant document management activities. At the API level, you can add or delete data fields on any template. Editable fields include text, checkboxes, and masked fields as well as various signature options and attachments.

Tokens Client

Bulk send

Bulk Send is a standard API feature in PandaDoc that allows developers to program the sending of hundreds of documents with just a few clicks. Create or modify one template that syncs with your CRM or other data source, personalizing your doc with custom, dynamic data, sending out hundreds if not thousands of documents in one fell swoop, continually streamlining and scaling your business as your customer base grows.

Close Deals


Webhooks help you to keep tabs on all of your docs pre and post-send. The PandaDoc API, unlike the WebMerge document API, supports webhook functionality so you can monitor document progress and stages, including when they have been opened, viewed, completed, and sent. You can also track individual pages viewed and every internal edit and change to any document or template.


The bottom line

Both WebMerge and PandaDoc are superb universal solutions for automating document creation and management, with strong security, great template collections, and a powerful collection of ready-to-use integrations. The all-in-one offering of PandaDoc compares favorably with WebMerge, however, the PandaDoc API offers a more robust and comprehensive interface for customizations and integrations, internal reporting and eSigning management which every enterprise requires for handling docs.

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