Introduction to Ecommerce Conversion Principles

This article will explore two ecommerce conversion principles that are essential for a highly converting website selling a good or service. It focuses on two specific areas of an ecommerce website and explores the reason why certain criteria must be met in order to enhance the user experience and statistical chance of a visitor making a purchase.

1. Keep the navigation simple

Your navigation is offering the user so much more than merely a portal around your website. It is representing the various pages and depth of content available on your precious site. Users are on the 'scent for information' on a website and therefore the navigation must not be too complex, such that users can scan, comprehend and make appropriate action to reach the information they seek accordingly.

Complexity is a conversion killer. Think of your own experience buying something online. Are you more likely to complete an online purchase if you can quickly locate and find what you are looking for, or would you be more likely to convert if you had to trawl through 40+ options?


  • Make your navigation simple to comprehend by using descriptive copy of the resulting action, keeping each option down to one or two words and using straightforward terminology. Overwhelming the user with choice and/or doubt of the outcome will put the user off.

  • Limit the length of the navigation to between three and seven headers and three or fewer subcategories.

  • Use web conventions where appropriate. That is stick to the well-known, universal symbols (for example the hamburger menu, magnify glass for search, universal share button).

  • Test the functionality. A navigation often has a lot of functionality and is thus a common place for dead links and other functionality issues. Rigorous browser testing can detect all of these.

  • Place your more important links first.

  • 'Contact Us' is typically found last in the primary navigation.


Sweat VAC  – This fashion website has a clear, ordered and descriptive primary navigation, which is very consumer orientated and just 5 options long. This makes it very easy for users to scan and understand each option.

Example navigation


2. Use clear and informative field validation error messages

The most user friendly websites are easy to use for all. Segmentation is key. Your website should be easy to use for someone who knows nothing about your industry, or for someone with limited web experience. Every user has a 'reservoir of goodwill', a breaking point, where they are no longer willing to invest their time in your website. A form is typically a hot spot for friction, due its relatively high cognitive demand. Field validation error messages play a vital role in the communication between the user of a website and the website itself. As a form can be such a sensitive part of the sales funnel, the quality of the messages is critical. It is extremely frustrating not being able to submit a form, with a lack of clarity as to why.


  • Make it as clear as possible to the user where the issue is. Blanket error messages at the top of the form are far less informative as to where the issue actually lies, for quick rectification. Compare this to clear field validation error messages, highlighted red (to grab attention), that are clearly associated with their respective field(s).

  • Clearly highlight all the issues. Some forms decide to highlight one error at a time, regardless of if there are more.

  • Offer real-time inline validation. Most forms will not inform the users of any issues until after they click submit. Such a lack of conversation on the websites part can be very frustrating for the end user and can severely hamper their progress down the sales funnel. Real-time inline validation helps people fill out forms more quickly (especially with less obvious fields), with less effort, fewer errors, and more satisfaction.

  • Make the error messages easy to understand. The user had an issue with the field in the first place, so an information message depicting the correct solution procedure is imperative. If a user still cannot complete the form, the chance of conversion is severely threatened.

Additional form Guidelines:

It is obviously beneficial to try to make your form as user friendly as possible in the first place, such that field validation error messages occur less frequently:

  • Use watermark copy when necessary, to prompt and guide users of a sensible entry.

  • Make it clear which fields are mandatory.

  • Ensure your form scales and performs well on mobile. Mobile forms are a hot spot for bugs that can severely hamper a user experience and your conversions.

Example: - Not only is the field validation error message red and positioned near to the culprit field, but it is also very informative of the solution.

Good field validation error message


I have discussed two important areas off a highly converting ecommerce website.

It is essential the user is presented with a concise and easy to understand primary navigation, with the most important elements at the beginning. Remember your primary navigation is offering so much more to the user than merely a portal around your website. It is suggesting the size and content of your website and is a major player in early user-website communication. Field validation error messages play an important role in communication between the user and the website when the former is completing a form. They must be informative and clearly show where the culprit field is, to ensure the users frustration is minimised and form completion is imminent.

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By Samuel Nickson of