How to Pre-Fill Forms with External Data Using APIs

Filling out an online form can feel repetitive. You type your email address, your phone number, maybe even your company details over and over. It wastes time and often leads to mistakes.

But what if your forms could automatically fill those details for your users? What if your forms felt smarter, faster, and easier to complete?

That is exactly what Formester’s Pre-Fill Forms with External Data Using API helps you do. It lets you pre populate fields in your web form using information from tools you already use, like your CRM, Excel, or Notion.

In this blog, I will explain how it works, why it matters, and how to set it up even if you have no tech skills.

What Does It Mean to Pre-Fill or Pre-Populate Forms?

When we say pre populate form or pre fill a form, we mean your form brings in information your system already knows — like a customer’s email address or phone number and places it into the form automatically.

That way, your users do not have to type everything again. It makes the whole form submission process quicker and more user-friendly.

Why You Should Use API Based Pre-Fill for Your Forms

Here is how this simple feature helps your business:

• Save time for your users

• Reduce typing errors

• Forms feel easy and quick to complete

• More completed forms and fewer drop-offs

• Faster lead capture, hiring, and order processing

• Happier customers and smoother workflows

Whether you are collecting leads, processing orders, onboarding clients, or hiring, auto fill form data makes the experience faster and easier for everyone.

How to Pre-Fill Forms with External Data Using API (Step by Step)

Setting this up in Formester is easier than you think. You do not need to be a developer.

Step 1: Open Your Form and Go to the Share Tab

• Log in to Formester.

• Open the form you want to pre populate.

• Click on the Share tab.

• Choose Pre-Fill.

Step 2: Select API Based Pre-Fill

• In the Pre-Fill options, select API Based Pre-Fill.

• Formester gives you a ready-to-use API link.

• You can connect this to your CRM, Excel, Airtable, Notion, or even another Formester form.

Step 3: Map Your Form Fields to Your Data

• Tell Formester which form fields should pull which data.

• For example, link the email address or phone number fields to the matching data from your CRM or spreadsheet.

Step 4: Share the Form URL

• Once your fields are mapped, share the form url.

• When your users open the link, the forms pre populated with their details.

• They simply review, complete any missing parts, and hit submit.

Where Can You Use Pre-Fill Forms in Real Life?

Pre-Fill is not just a fancy feature. It solves real problems for businesses every single day. Here are common scenarios where it saves time, reduces errors, and helps you win more business:

1. Lead Capture and Quote Requests

Imagine a potential customer fills out an inquiry form on your website. You already have some of their details stored in your CRM. Instead of asking them to type everything again, send them a pre-populated form. Their email address, phone number, and other details automatically fill. They only need to review and submit. You look professional, and your chances of closing the deal improve.

2. Job Applications and Recruitment

Hiring can be a paperwork headache. But with Pre-Fill, you can speed up the process. If a candidate applied earlier or submitted a resume, pull their details from Excel or another form and pre populate your job application form. The candidate saves time, and your team stays organized.

3. Client Onboarding

First impressions matter. When welcoming a new client, send them a web form that already has their basic details filled in — straight from your database or CRM. They complete the rest, and you deliver a smooth, professional experience.

4. Order Processing for Existing Customers

For repeat customers, filling the same forms repeatedly is frustrating. Pre-Fill lets you send them a form url where their contact and delivery details are already filled in. Fewer errors. Faster order processing. Happier customers.

5. Internal Team Workflows

Even within your team, forms are everywhere. Onboarding employees, submitting requests, updating records. Pre-Fill ensures your team does not waste time re-entering the same details. It keeps your processes fast and error-free.

Final Thoughts

Filling out forms is a necessary part of doing business. But it should not feel like hard work for your customers, employees, or clients. With Pre-Fill Forms with External Data Using API, you can turn your forms into a fast, seamless experience.

Think about how much time your team spends sending forms back and forth. Or how many potential leads you lose because people do not want to fill long forms manually. Now imagine a world where your forms automatically fill with the information you already have. No typing. No confusion. No delays.

Whether you are generating forms for lead capture, customer onboarding, hiring, or order processing, pre-filled forms save you time, reduce errors, and make your business look more professional.

This feature works with your existing tools like CRMs, Excel, Airtable, Notion, or even other Formester forms. You stay in control of your data, your forms stay smart, and your users stay happy.

It does not matter if your users open the form URL on Google Chrome, mobile, or any other device — the experience stays smooth and consistent. Sign up for Formester today and set up your first pre populated form in minutes.