How to build a HubSpot lead capture form using Claude in 10 minutes

You want a lead capture form that looks good, matches your brand, and drops new contacts straight into HubSpot. The old way meant wrestling with a form builder or waiting on a developer. Here is how to do it in about ten minutes using Claude and flng.ai.

What you will need

• A Claude account (the free tier works fine for this)
• A flng.ai account with a trial or subscription
• A HubSpot account you can connect to

Step 1: Ask Claude to build the form

Open Claude and describe the form you want in plain language. Be specific about the fields, the style, and the fact that you need a single HTML file. A prompt like this works well:

Build me a lead capture form as a single HTML file. Fields: first name, last name, email, company, and phone. Make it clean and modern with a coral accent color. Include inline validation and a submit button that says "Get started."

Claude will generate the full HTML. Read it over, ask for any tweaks, and when you are happy with it, ask Claude to give you the finished file.

Step 2: Save it as an HTML file

This is the step people forget. Whatever you build, ask your AI to save the work as an HTML file. That single file is what you upload next. Without it, you have nothing to publish.

Step 3: Upload to flng.ai

Log in to flng.ai and upload your HTML file. The platform cleans and validates the code, then detects every field you are collecting and lines them up for mapping. This usually takes under a minute.

Step 4: Map your fields to HubSpot

Connect your HubSpot account and map each form field to a HubSpot contact property. First name maps to First Name, email to Email, and so on. If you need a property that does not exist yet, you can create it right there without leaving the page.

Step 5: Publish and embed

Hit publish. You get a live URL and an embed code instantly. Paste the embed code into your website, WordPress, Webflow, or an email, and your form is live. Every submission now updates an existing contact or creates a new one in HubSpot in real time, with bot filtering and secure hosting handled for you.

That is it

Ten minutes, no code, no developer. The AI did the design and the markup, and flng.ai did the hosting, the spam protection, and the CRM sync. When you need to change something, just ask the AI to update the file and re-upload it.