Invoice AI Documentation

Everything you need to create, send, and manage invoices with Invoice AI — from your first invoice to full API automation.

Invoice AI is a global invoicing platform for freelancers and small businesses. Create professional invoices in seconds using AI assistance, manage your customer catalog, track payment status, and automate your billing workflow through a Stripe-shaped REST API.

Quick Start

Create your first invoice in under 5 minutes

API Reference

Explore the full REST API

AI Invoice Creation

Let AI draft your invoices from plain text

Webhooks

React to invoice events in real time

Get Started

1. Create your account

   Sign up at invoice.horizonpay.co or create your first invoice as a guest — no account required to start.

2. Set up your business profile

   Add your business name, country, and currency. Invoice AI auto-selects your currency based on your location.

3. Create your first invoice

   Use the invoice builder or type a plain-English description like “Invoice Acme $5,000 for brand design” and let AI fill in the details.

4. Send and get paid

   Finalize your invoice to assign an invoice number, then share the PDF link or email it directly to your client.

Explore by Topic

Invoices

Lifecycle, statuses, and numbering

Customers

Manage your client list

Products & Prices

Build a reusable catalog

Business Profile

Configure your business details

API Keys

Authenticate API requests

Email Invoices

Send invoices to clients