OptiDrop

Free Invoice Generator Online — Download PDF Invoice

Create professional invoices in minutes. Add your business details, line items, tax rate, and currency — then download a clean PDF invoice instantly. 100% free, no sign-up required.

Line Items

Description Qty Unit Price Amount
Subtotal: $0.00
Tax (18%): $0.00
Total: $0.00

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Free Invoice Generator — Create Professional PDF Invoices Online

OptiDrop's Invoice Generator lets you create polished, professional invoices in minutes without any design skills or expensive software. Simply enter your business details, add line items with quantities and prices, select your currency and tax rate, and download a clean PDF invoice ready to send to your clients.

Multi-Currency Support

Support for 10+ currencies including USD, EUR, GBP, INR, AUD, CAD, JPY, CNY, BRL, and MXN. Whether you are billing locally or internationally, the invoice generator formats everything correctly with the right currency symbol.

Automatic Tax Calculation

Select from common tax rates (0%, 5%, 10%, 15%, 18%, 20%) and the tool automatically calculates the subtotal, tax amount, and grand total. No manual math needed — just focus on your business.

Frequently Asked Questions

A professional invoice should include your business name and contact details, the client's name and address, a unique invoice number, the invoice date and due date, a detailed list of products or services with quantities and unit prices, the subtotal, applicable tax rate and amount, and the total amount due. Payment terms and accepted payment methods should also be specified.
Invoice numbers should be unique and sequential. Common formats include simple numbering (INV-001, INV-002), date-based numbering (INV-2024-001), or client-based numbering (ACME-001). The key is consistency — choose a format and stick with it. Never reuse an invoice number, as this helps with bookkeeping and tax records.
The due date depends on the payment terms you set. Common terms include Net 30 (due 30 days from invoice date), Net 15 (due in 15 days), Net 60, or Due on Receipt. For freelancers, Net 15 or Net 30 is most common. Always clearly state the due date on your invoice to avoid payment delays.
An invoice is a bill sent to a client requesting payment for goods or services — it is issued before payment is made. A receipt is proof of payment that is issued after payment has been received. Invoices are used for accounting and record-keeping before transactions are complete, while receipts confirm that a transaction has been finalized.

Invoice Generator — About This Tool

The OptiDrop Invoice Generator is a free online tool that helps freelancers, small businesses, and entrepreneurs create professional GST-compliant invoices in minutes. Add your business details, client information, line items with quantities and prices, select your currency and tax rate, and download a clean PDF invoice ready to send. The tool supports 10+ currencies, automatic tax calculation, and saves your data locally so you can resume editing later.

How to Use the Invoice Generator

  1. Enter your business name and address in the left column, and your client's name and address in the right column.
  2. Fill in the invoice number, invoice date, due date, and select your preferred currency from the dropdown.
  3. Add line items by clicking "Add Line Item" — enter the description, quantity, and unit price for each product or service. The totals update automatically.
  4. Select the appropriate tax rate, then click "Download PDF" to save the invoice or "Copy Text" to copy it as plain text.

Frequently Asked Questions

What is a GST-compliant invoice and what details must it include?

A GST-compliant invoice in India must include the supplier's name, address, and GSTIN (GST Identification Number), the recipient's name and address, a unique sequential invoice number, the date of issue, a description of goods or services, the quantity and unit price, the taxable value, the applicable GST rate (CGST, SGST, or IGST broken down separately), and the total amount. While this generator creates a clean professional invoice, you should manually add your GSTIN and the recipient's GSTIN if you are registered under GST. The tool calculates the tax amount automatically based on the rate you select.

Can I add multiple line items to a single invoice?

Yes, you can add as many line items as you need. Click the "Add Line Item" button to add a new row to the table. Each line item has its own description, quantity, and unit price fields. The subtotal, tax, and total are recalculated automatically every time you change any value. You can also remove any line item by clicking the trash icon on that row. This makes it easy to create detailed invoices for projects with multiple products or services, such as a web development invoice that lists design, coding, and testing as separate line items.

Which currencies are supported?

The invoice generator supports 10 major currencies: US Dollar (USD), British Pound (GBP), Euro (EUR), Indian Rupee (INR), Australian Dollar (AUD), Canadian Dollar (CAD), Japanese Yen (JPY), Chinese Yuan (CNY), Brazilian Real (BRL), and Mexican Peso (MXN). The currency symbol is automatically applied to all amounts on the invoice and in the downloaded PDF. If you need a currency that is not listed, you can download the PDF and manually edit the symbol using a PDF editor. The tool is designed for international use and handles currency formatting correctly for all supported options.

How should I handle invoice numbering for my business?

Invoice numbers should be unique and sequential for proper bookkeeping and tax compliance. Common formats include simple sequential numbering (INV-001, INV-002, INV-003), year-based numbering (INV-2026-001), or a combination with client codes (ACME-INV-001). The key rules are: never reuse an invoice number, keep the format consistent across all invoices, and maintain a log of all issued numbers. This tool lets you type any invoice number you want, so you can follow whatever numbering system your business uses. For GST compliance in India, sequential invoice numbering is mandatory, and gaps in the sequence may be flagged during audits.

Last updated: June 2026