Frequently Asked Questions - Find your answers here

We've complied a list of the most common questions we receive and some useful hints for invoicing online!

Our aim here is to leave you with no question unanswered. Although invoicing itself can be straightforward, there are a myriad of functions, tools, and add-ons that we've created to simplify and enhance the user and client experience. Check out our Frequent 5 questions to your right, and additional FAQ's below. If you find there is a question that is not listed below, please don't hesitate to contact us directly at [email protected]

Knowledge Base
How do I set up online payment?
To set up online payment, you’ll need to integrate with a payment gateway. The payment gateway will help facilitate a successful transaction between you and your client. The integration page can be found in the “Settings” section under “Online Payments”.
What are the main differences between Invoice Ninja and Ninja Pro?
Some of the main differences include an upgrade to 10 professional invoice template designs, removal of Invoice Ninja branding, and highly personalized advanced settings.
How can I best utilize the product library?
The product library is designed to help keep track of the products you frequently use when invoicing clients. To use the library to your advantage, it’s best to store details of your most popular products in order to ensure a quick and easy selection when creating an invoice. You can store an unlimited amount of products, so feel free to even add the products you use occasionally, thereby creating hassle free invoicing always.
How do I set currency individually per client?
Currency per client can be set in the client’s personal details section. This form will open when you first create a client, and you can access the folder at any time in the client section if you select the individual client and choose to edit client details.
  • Why should I upgrade to Ninja Pro?

    Ninja Pro is the total package. Although we’ve made the free version quite robust, the Pro version allows for more creativity, personalization, and setting preferences which can further individualize your company and bring your invoicing game to the highest level.

    The free version of Invoice Ninja has an extensive list of features available, however there are some definite perks to upgrading. Ninja Pro offers 10 professional invoice templates, numerous advanced settings options, removal of Invoice Ninja branding, custom URL’s, multi-user account access and more. For the full comparison chart, click here:

  • What are partial payments?

    Partial payments allow your clients to partially pay their bill at different times, as opposed to requiring full invoice payment in a one-time transaction. You can locate the “Partial” box at the top of an existing or new invoice. Simply enter the partial payment amount, and the live PDF will adjust immediately. After a client pays the partial amount, the invoice will update itself to reflect the remaining balance due.

  • How do I add my company logo?

    Your company logo can be uploaded in the company details section. Simply upload the logo from a file on your computer, save the file and you’ll be able to view the logo in your invoices instantly. File types supports are JPEG, GIF, and PNG. Recommended logo size is: 200px width by 120px height.

  • How do I locate my API key?

    You can generally locate your API Key under your Account Settings or the personal details section of your payment gateway site i.e.,,, etc... It’s important to note to use your secret API Key, rather than your publishable API Key and ensure your account is “live” and not in any test or demo mode.

  • What is token billing?

    Token billing enables credit card storage within a gateway so your card can be charged at a later date.

  • How do I use the Tasks section?

    Once you select or add a new client under the “New Task” tab, simply click the “Start” button and the timer will begin. The Task will record project length for various clients and store the information in the Task library. You also have the option to manually add projects you’ve timed for clients. For this option, choose “Manual” instead of “Timer” and you’ll see a form open up in the dropdown.

  • Does archiving a client affect the client’s balance?

    Archiving a client does not affect the client’s balance. Deleting a client will remove all client details.

  • How do I convert a quote to an invoice?

    In the Quote section, select a quote from your quote library, locate the “Action” dropdown on the far right and select “Convert to Invoice”.

  • How do recurring invoices work?

    When creating a new invoice, at the top section of the page you’ll notice a checkbox next to the word “Recurring”. When you check this box, new settings will open up above including “How Often”, “Start Date” and “End Date”. Here you can set up the specific details per invoice for a recurring invoice. Your options include Weekly, Two Weeks, Four Weeks, Monthly, Three Months, Six Months and Annually.

  • How do payment terms work?

    When you create a new client, you have the option to set up payment terms. Payment terms help you clarify the due date and terms of your invoices for your clients. Invoice Ninja offers pre-set payment terms in the New Client form. There you can choose from our options ranging from Net0 to Net90. You also have the option to determine your own personalized payment terms on the Invoice creation page or within your settings section.

  • How do I apply credit to a payment?

    When you create a new payment and select a current client with credit, on the “Enter Payment” page you can choose “Apply Credit”.

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