Readability versus The Robot: The Flesch Reading Test

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I first came across the Flesch Reading Ease Test thanks to a combination of pride and annoyance. Messing around with Yoast’s WordPress plugin, I was confronted by the following message:

“The copy scores 68.9 in the Flesch Reading Ease test, which is considered OK to read.”

Flesch reading test in Yoast analyser

Screenshot taken 08/01/2014 of www/

“OK to read?” I thought, “How dare you?” So, fueled by a heady mix of disbelief and irritation, I set out to learn more about this presumptuous little test and why it didn’t recognize that my content was, frankly, super stellar. The results were interesting and spoke volumes about why many outdated approaches to “SEO content” need to change in the Hummingbird age. Allow me to elaborate…

What is this Flesch test thing?

First things first, let’s just clear up what this test is. SEJ has highlighted a few readability tests in the past and the Flesch Reading Ease Test is just one of them. It was developed to gauge how easy it is to read a piece of text, using a simple (but not very sexy-looking) formula:

206.835 – 1.015 (total words/total sentences) – 84.6 (total syllables/total words)

As a word nerd (not a numbers whiz), this doesn’t make much sense to me either. Yet what it boils down to is actually very simple:

  • More words per sentence = less readable
  • More syllables in a word = less readable
  • Fewer words in a sentence = more readable
  • Fewer syllables in a word = more readable

Under the tyranny of the Flesch Reading Ease Test, short sentences comprised of monosyllabic words are rated as the most readable. Meanwhile, long sentences made up of polysyllabic words are considered the least readable.

Why does it matter?

I may have a personal bee in my bonnet about this test, but why does it matter to you and your SEO practices? Well, it transpires that readability is a ranking factor – and that Google have quite a neat little tool all set up and ready to gauge the readability of your content. Take a look at the page-level ranking factors in last May’s handy infographic. Grammar and spelling, along with readability, all have an effect on your page rank.

Equally, if the chaps over at Yoast think that it’s a factor worth including in SEO page analysis, there’s probably something to it…

It’s not entirely clear what test Google uses to rate readability, but they’re obviously using something. Just take a look at this advanced search function:

Readability advanced search

Screenshot taken 06/01/2014 of

As you can see, users can choose to filter their results according to the readability level and choose to annotate search results with each website’s score:

Readability displayed in SERPs

Screenshot taken 06/01/2014 of

How this affects ranking – and to what degree – is unclear. But keeping things short, sweet, and monosyllabic is likely to be in a website’s favor.

Or is It?

The “short and sweet”, “lowest common denominator” sentiment is not a new thing. Even away from the web, writers and students are frequently advised to “Keep It Simple Stupid”. Writing for the widest possible audience makes a certain amount of sense, but is there really any merit in it?

Well, yes and no. I’m just one copywriter, yet, in my humble opinion, there’s a lot to be said for knowing your audience, using a little common sense and not patronizing your demographic. If you write for the lowest common denominator across the board, you run the risk of alienating, boring, and irritating your target readership.

For instance, if you’re selling retro sweets to a broad market, this approach is fine. However, if you’re writing to engage clever people with an interest in online marketing (just like your good selves), then it’s not always such a good idea.

Example Time!

Let’s look at how this works in practice. I’ve taken the first sentence from Jayson DeMer’s helpful post on content creation to demonstrate. Here’s Jayson’s version:

“One of the effects of the rise of popularity in content marketing has been a surge in content curation; the practice of aggregating similar content into one place in an attempt to create new value.”

As you can see, this is a long, complex sentence, with plenty of polysyllabic words; aggregating, curation, popularity etc. Now, here’s a radically simplified version:

“Content curation puts different content in one place. Content curation is done to add value for users. This is done more and more. This is because content marketing is growing more popular.”

Now, according to’s tests, my horrible, simplified version is more readable. But let’s be honest, it flat-out isn’t. It explains less clearly, it’s clunky and an all-round horrible reading experience. So much for “readability”. Point proven!

Readability comparison

Screenshot taken 08/01/2014 of

The Take Home Message

As we’ve seen, readability for search engines and readability for real human beings are two very different animals. While ‘robot readability’ is a ranking factor, it is just one factor among hundreds. Bounce rates are a big deal, too! If your visitors take one look at your plodding text before running for the hills, this is going to have an impact on your place in SERPs.

So how should you approach readability when writing for the web?

Write for Readers, not Robots

Grafitti robot

Image credit: Steve Rainwater. Used under license.

Here’s the grand finale: In a Hummingbird world, it’s far more important to provide a high-quality, engaging and target market-appropriate experience. Quick, techie fixes and SEO shortcuts are increasingly pointless. When you’re writing, forget about search engines and just write for your audience (make sure you know your sector and target market inside out first though!). You’ll convert more, get shared more and enjoy a more authoritative reputation as a result. Make sure your content is cracking, then worry about SEO value.

As for the Flesch Reading Ease Test, I think you can safely disregard any little Yoast messages which underrate your excellent content. Monosyllabic, five word sentences my be technically easier to read, but they do next to nothing for genuine readability, let alone audience engagement. So next time you’re writing up some hot new site copy or penning an industry-shaking blog: do it your way, for your target market and don’t let a robot tell you how to write.

Featured image credit: Used under license.

Holly Hartzenberg
Holly is the co-founder of To Your Heart's Content, a team of slicker-than-your-average digital copywriters. When she isn't providing top drawer copywriting services Holly can... Read Full Bio
Holly Hartzenberg
Holly Hartzenberg
Holly Hartzenberg

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  • Scott McKirahan

    Hahaha. I’m with you here! If Jayson DeMer wrote like that second, simple sentence, I’d never read another word he wrote. When it reads like it was meant for grade schoolers, I assume it was written by one and the author and website lose all credibility.

    • Thanks for the read, Scott. Couldn’t agree with you more, a reader knows when they’re being patronised. Real life, outside world, ad copy gets me so riled so often – it seems to be one of the worst culprits! I know that businesses are often putting all of their eggs in one basket with a homepage or a piece of important content, but catch-all, one-size-fits-all, dumbed down copy isn’t going to entice anybody…*grump over*

  • Normal version:
    Awesome work, Holly. It’s great to see you contributing to SEJ, too. I’ve always wondered about Yoast’s copy score and whether it should be taken as gospel, and this has answered the question. It’s a good thing to dispel, especially as a lot of people may simply try and get that number to 100 without thinking of its actual readability afterwards.

    Flesch Reading Ease Test friendly version:
    Well done. You’re on SEJ! So true. I agree! People must be careful.


    • Haha! I like your “simplified” version, Steve. 🙂

    • Haha!

      Thanks Steve. No word lessons for you though. You’ve cracked it!


      (Mr Morgan, my gratitude for your most eleemosynary comment knows no bounds. Quite candidly, I do not deem you to be requiring any persuasion of instruction on the bailiwick of orchestrating a (to hyperbolise triflingly) transcendentally stupendous specimen of content, for, to all appearances, you most convincingly convey the impression of (nay, demonstrate all the hallmarks of) apprehending and assiduously fathoming the art of penning a superlative iota of most exquisite copy.)


  • Great article! There’s still a long road for machines and maths to become something really capable of judging something so complex as “readability”. Professionals should never compromise for a simple score, its the machine judging capability that must be improved. Better have a little less traffic because you are lacking “robot readability” than having readers wonder if you finished grade school.
    I will make sure this gets passed on ;). Looking forward to your next articles!

    • Thanks Emmanuele!

      At university I had a lecturer who specialised in computer linguistics, he seemed to think that those damn robots would be creating readable articles all on their own one day soon – novels, poetry, editorials the lot! A very sad idea – there’s just no substitute for real human fluidity, personal style and understanding. It goes such a long way when talking to a real audience.

  • Jesse Stoler

    Fantastic read Holly! “Write for readers, not robots” is essentially my unofficial mantra. Since the voices of Google consistently they say want to provide the best user experience possible, why would anyone write for a spider as opposed to a user?

    • Thanks Jesse!

      People > Spiders, Readers > Robots, I think there might be a nerdy t-shirt line in the offing. I quite agree with you, the whole concept of a readability score based on equations seems really contradictory to the push for a UX focused approach. Any idea what real use the readability search function might have? (Copywriter here, no search engine super-whizz!)

  • Thank you for the example in Jayson’s sentence. I’ll be writing all day today and this article will help me break things down. I have a habit of writing long sentences. I been avoiding the readability score on Yoast because I have not fully understood what I needed to do to clean things up. Great post.

    • Thanks for the read Andrew!

      I really wouldn’t advise breaking down your writing to follow what I did with Jayson’s sentence. That was an example I used to demonstrate that shorter, simpler sentences don’t necessarily make great readable writing.

      Keeping your content snappy is great, but don’t sacrifice fluidity and sense to dumb your content down. My approach is to write a first draft naturally, then read your content back carefully, from the perspective of your target audience. Be ruthless. Anything which makes you pause and go “huh?”, forces you to stop and reread or makes you drift off out of boredom – cut it and phrase it more concisely. If it’s not broke though, don’t fix it – give your readers (and your understanding of them) some credit instead!

      All the best!


  • This is great! I believe that it is extremely important to write for readers rather than robots. Don’t get me wrong, robots are always great to have because they can generate traffic and help you be successful but I believe real people can do the same job if not better because they actually have emotion behind the things they say about a company’s product/service they offer. Also, it important to keep things simple but to still convey they message that you are wanting to.

  • This a great article. People sometime write with only SEO in mind and consequently miss the mark. I believe it is far better to strive for great content that your target audience will actually want to read.

  • Paula Allen

    While a Flesch score needs to be taken with a grain of salt, as does any machine-generated metric, it does have some value: it ascertains the reading level of your writing. You state that what’s important is to “provide a high-quality, engaging and target market-appropriate experience,” and certainly that’s true. But reading level IS a factor in matching your target market. You want to create content that fits both their preferences and what’s natural among top competitors. I don’t disagree with you, just recommend not throwing out the baby with the bath water.

  • Does it has something to deal with the Meta Description as well as the Title Tags?