Functional testing for emails is crucial for any email campaign. How do you make sure what your clients and customers are seeing is what you designed and sent? This article will cover some basics of functional testing and the most common mistakes people uncover.
What is functional testing for emails?
Functional testing refers to a specific software validation test strategy. It involves comparing the software’s outputs (in this case, your email) to the expected result based on your input. Functional testing doesn’t look at what the software is doing, only at what goes in and what comes out, so it’s limited in spotting where specific software bugs are in the program. However, it’s fast and cheap, and it will tell you if there are bugs, so you can run more in-depth tests if necessary.
People run functional tests for emails every time they make a change to them. This might seem like a lot at first, but once you’ve set up your testing process, much of it can be reused. You can even automate many testing tasks to save even more time.
Why is functional testing for emails so important?
Emails are a significant part of your communication with your audience, whoever they may be. Errors in emails reduce your professional reputation, whether from technical bugs or simple spelling mistakes. If they’re significant enough, they can even disrupt your operations. For instance, if the software you’re using to send out your email doesn’t hide the email addresses of everyone you sent it to, then you’ve just sent personal contact information to many people who were never supposed to have it.
In addition, the people receiving your email might be using different email providers, browsers, and operating systems, all of which can make your emails appear unexpectedly. Testing your emails through all these different combinations will uncover bugs and errors, plus any mistakes in the email itself, before you send it to hundreds or thousands of people’s inboxes.
What to look for when testing your emails
There are a few different categories to keep an eye on when planning your functional tests. Some are listed below, but as in most things, your list will vary depending on your needs. We’ll explore some of the most common mistakes in the next section. Here are some things to look for:
- Spelling and grammar mistakes
- Formatting errors
- Broken links
- Email field restrictions
- Form validation
- Regular expression (RegEx) validation
- Low-quality images
- Missing alternate text for images
Top eight most common mistakes in emails
Next, we’ll go over details on some of the email errors that are most often caught in functional email testing, and some tips to get you started on fixing them.
1. Spelling and grammar errors
Sometimes spelling mistakes and grammatically incorrect phrases sneak past filters, and spelling checkers and grammar tools aren’t perfect – sometimes they make mistakes too. Email testing allows you to look over the email as it would look to someone else, making it easier to spot any errors in the text you may have missed.
Grammar and spelling checkers like Grammarly are still helpful tools, but if you’re unsure if something’s correct based on its feedback, you might have to rephrase something or look for more information. The correct spellings and rules also depend on geographic location, so make sure you’re using the conventions your audience expects.
2. Email formatting problems
Emails display according to the email client your recipient uses, so the email that looks great in your inbox might run into issues in someone else’s. Text may wrap unexpectedly, images might not be shown how you intended, and more.
The biggest problem with email formatting is having an incorrect email width. The standard width is 650 pixels wide, so if your emails are narrower or wider than that, it might show unexpected formatting errors.
3. Broken links
Sometimes, the links in your emails might not be set up correctly, or the link address may have changed. Maybe someone forgot to update the links in the template. No matter the cause, links are one of the most crucial parts of your email since they are what directs your recipients to take the following action, whether it’s leaving a review, reading an article on your site, or reaching out. Functional email testing can be used to automate checking links are still working, although depending on the email, you may have to check they’re the correct links yourself.
4. Email field restrictions
Different email clients may have different limitations. For instance, the email client you’re using to send out your emails may restrict the number of characters in an email address, but someone on your email list uses a longer address. Figuring out how the email client would handle that situation in testing is better than finding out when you’re sending out critical information, which gets lost.
5. Form validation
If your email contains a form, there are a few additional things you’ll need to watch out for. Any time users place input into a field, you want to ensure the inputs are what you want them to be.
There are two different levels of restricting the form inputs. The first is the entire form – ensuring the required fields are filled in before the form can be submitted. The second level is providing each area only accepts the suitable types of inputs. To do this, you might restrict the number of characters and the type permitted for each field. The following section talks about this in more detail.
6. RegEx validation
Regular expression (RegEx) validation refers to checking that strings match the format specified by a regular expression, a snippet of code that defines the limits of the acceptable values in the string.
An example would be, checking if a date is an input in a YYYY-MM-DD format. The input string is compared to the RegEx code, often using a RegEx validator tool. The RegEx code ensures the string has numbers where the year, month, and day are supposed to be, and there are dashes between them. It also checks that the numbers for each variable are within the constraints – so putting 13 in for the month wouldn’t return a match since there are only twelve months in a year.
7. Image quality
Another common problem has to do with having images that are the right size and quality. If the images are of higher quality and size than necessary, it will slow download times for your email. However, if you on the side of low image quality, your email won’t look professional.
Remember the standard email width mentioned above to get the right size images for your emails. Your images shouldn’t be wider than 650 pixels and should only be that wide if they’re meant to stretch across the entire email template.
To see if your images are too small, run a quick test email and see how they look. Are sharp edges in the image clear and crisp? Does the image look clean and focused? If not, you might need to get a higher quality image or switch image formats from a .jpg to .png, especially if your image has high contrast or sharp lines and shapes.
8. Alternate image text
Alternate image text is metadata attached to the images in your email, if you have them. It’s used to describe what the image is displaying if the image can’t be loaded or if the person receiving your email can’t see it. The alternate text is fed into programs used to read text out loud to people, so it’s essential to include it.
It’s also important because some email clients don’t automatically load external content, including images, in emails to protect their users. In this case, the alternate text will show and make people feel more comfortable loading the external content so they can see what you intended the email to look like. It helps establish trust with your recipients in your technical ability.
How to perform email functional testing with Mailosaur
Mailosaur provides software to help with functional testing that can be used to set up servers and unlimited email addresses so you can run your own tests with a wide range of email clients and browsers and cover all your bases. Our software works with other testing frameworks you might already use, like Playground and Cypress, so it’s easy to automate your tests. Contact us today to learn about how our products can make your emails error-free!