Business Writing 2021-04-08 00:00

Mailchimp and ProWritingAid: Automating the Holy Grail of Style Guides

Mailchimp's Style Guide Welcome

When it comes to customer-facing writing, Mailchimp are pioneers. Their offbeat humor and conversational voice have helped them grow to over $750 million in revenue.

Making sure that a team of over 1,200 people speak with one voice is no small feat. One of the keys to their success is their style guide, which UX Writing Hub describe as “the holy bible of content style guides.” In fact, wherever you look across the internet, Mailchimp’s style guide receives praise.

  1. Why Use Automated Style Guides?
  2. It Starts with the Name
  3. Automating Simple Rules
  4. Checking Tone
  5. Tricky Numbers
  6. Writing for Translation
  7. Conclusion

Why Use Automated Style Guides?

Any company of a reasonable size needs a style guide to guarantee that their external (and internal) communications are consistent. But a style guide is only half of the solution. Many a style guide sits unread, gathering dust in the stationery cupboard. The second half of the puzzle is implementing the training to ensure that people follow your style guide, and that can be hard work and expensive. Mailchimp’s style guide alone has over a hundred rules. You can’t expect everyone in the organization to memorize them all. Many organizations struggle to get their employees to remember one vision statement.

Ensuring style guides are actually followed is a problem that we at ProWritingAid have seen in many organizations—the larger the organization, the bigger the problem. That’s why we’ve developed our automated style guide tool.

With our automated style guide, you can convert your style guide into a living, breathing set of rules that will automatically run on every piece of writing in your organization. Combined with our browser and word processor extensions, this means that whenever someone accidentally breaches the style guide, they’ll see a highlight in their text with the suggested change. This significantly increases the consistency of customer-facing communication across your organization, and significantly decreases the likelihood of a “whoops” moment.

Mailchimp Style Guide Rule for Rockstars

Some other tools allow you to implement simple text matching rules, but ProWritingAid goes much further. Our rules can capture complexities such as the context a word is used in and can make powerful transformations, including changing the part of speech of words and formatting numbers.

“The holy bible of content style guides” seemed like a formidable test of whether our style guide was feature complete, so we decided to see if we could pass with flying colors.

It Starts with the Name

For many companies, their style guide starts with their name. Mailchimp is no exception.

Mailchimp Style Guide Rule for Brand Name

For Mailchimp, this is even more important because as they’ve changed the spelling over time, they need to make sure that all their texts reflect this change. It’s easy for old spellings to lurk around like a bad smell. This is an easy rule to create in ProWritingAid.

Mailchimp Style Guide Name Rule Automation

Automating Simple Rules

Mailchimp’s word list also adds a variety of other simple rules in the format Not X, but Y. For example:

  • checkbox, not check box
  • coworker, not co-worker or co workers
  • website, not web site

ProWritingAid’s style guide allows you to include optional tokens and match different forms of a word in one rule. So you can write one simple rule that matches multiple variants of a word, e.g. co-worker, co workers, co-workers, co worker.

Mailchimp Style Guide Hyphen Rule Automation

Mailchimp’s style guide includes a great many phrases that might be used accidentally by anyone. With great humility, they even admit that they used to use “automagical” a lot, and they’re embarrassed about it.

Mailchimp Style Guide Words to Avoid: Automagical

So we can cover a reasonable number of corrections with fairly simple rules. But that’s where the easy part ends.

Some of Mailchimp’s style guide rules are more sophisticated. For example, they ask employees to follow the grammatical rule of using “add-on” (hyphenated) for the noun and adjective form, and using “add on” (two separate words) for the verb form:

  • I will add on your bonus, but don’t see it as an add-on benefit.

This is where many people will start to get a little fuzzy in their understanding. Maybe you remember it from school, but maybe you don’t. The average person would likely struggle to tell you the difference between an adjective and a preposition if you stopped them in the street and asked them.

Fortunately, there’s no need to spend weeks educating your team about parts of speech. With ProWritingAid’s style guide, your team doesn’t need to know the difference. We allow you to create rules that only match words when they’re used in a certain way, e.g. as an adjective. So here we can set up a rule that only highlights “add on” when it’s being incorrectly used as an adjective (modifying a noun) without a hyphen.

Mailchimp Style Guide Rule Automation Hyphens

Checking Tone

One thing that sets Mailchimp apart is their conversational tone. Mailchimp have some good guidance around how to achieve this.

Active voice

Mailchimp says “Use active voice. Avoid passive voice.” This is good advice whatever you’re writing, but it’s something that many people struggle with. ProWritingAid provides built-in checking for passive voice.

Mailchimp Style Guide Passive Voice Rule

Mailchimp Style Guide Passive Voice Rule Automation

Write positively

Mailchimp’s style guide says “Use positive language rather than negative language.” They specifically say that you should avoid words like “can’t,” “don’t,” etc. This is a great suggestion, and easy to implement in ProWritingAid’s style guide with a friendly reminder.

Mailchimp Style Guide Positivity Rule Automation

In fact, ProWritingAid can go even further. When you’re writing documents like sales emails where positivity is important, we give you a positivity score and a target range.

Positivity Goal Ranking

Slang and jargon

Mailchimp advise writing “in plain English,” avoiding unexplained technical terms and slang. In fact, ProWritingAid already advises against a large number of jargon phrases, so you can be sure that there’ll be no opening of kimonos or paradigm shifts in your organization. Any other jargon that should be avoided can be easily turned into rules.

Mailchimp Style Guide Rule Jargon Automation

Tricky Numbers

Style guide rules for numbers can be difficult to automate. Fortunately, ProWritingAid rises to the challenges presented by Mailchimp’s style guide.

“Spell out a number when it begins a sentence. Otherwise, use the numeral. This includes ordinals.”

There are two challenges here: identifying a number only at the start of a sentence, and converting a number to a text representation and vice versa. ProWritingAid can do both, with a single correction suggested for the end user:

Mailchimp Style Guide Numbers Automation

This rule can also be applied to ordinals (like first, second, third).

What about longer numbers? Here’s another rule in the Mailchimp style guide:

  • “Numbers over 3 digits get commas”

ProWritingAid can handle this because our software allows matching of specific number types and changing their formatting. Here’s an example using the number 1000:

Mailchimp Style Guide Numbers Automation 2

Writing for Translation

Mailchimp’s section on translation-friendly writing is full of useful advice. These are the sorts of things that can be really important for international companies, but are really easy to forget.

For example, Mailchimp suggest:

Mailchimp Style Guide Sequences Rule

This is quite a specific rule and can be easy to accidentally break. It may also seem like a difficult thing for us to check automatically. Luckily, ProWritingAid’s rules can handle cases like this too.

Mailchimp Style Guide Sequences Rule Automation


We really like Mailchimp’s style guide. It’s completely public and available under a Creative Commons license. You can also find it on GitHub. If you’re going to develop your own style guide then we recommend that you take a look so that you have a good idea of what a quality style guide looks like.

ProWritingAid’s automated style guide checker is powerful enough to handle even the most tricky rules we found. That’s one of the reasons that the American Psychological Association (APA) also selected us to automate their style guide in their product Academic Writer.

We hope this has given you a taste of what’s possible with our automated style guide. If you have a style guide you’d like to automate then get in touch. ProWritingAid can help.

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