Friday, May 2, 2008

Testing the readability of your copy

To produce clear writing, you need to produce more readable writing. Readability is a prerequisite to clarity.

It is fortunate that readability can be measured. There are several tests available; I recommend Flesch Reading Ease, which was designed by Rudolf Flesch (photo), the famous plain-language consultant. It is based on solid psychological research, not abstract theory.

It is the world’s most widely used test – the standard readability test used by the U.S. Department of Defense and many other government organizations. Microsoft has built a modified version of the test into Word.

Here are a few sample ranges of test scores, from higher readability (top of list) to lower readability (bottom of list):

60s Reader’s Digest
50s Time magazine
40s The Wall Street Journal
30s Harvard Law Review; white papers
20s IRS forms; academic papers
10s Many high-tech web sites

To test your copy, all you need is a PC running Microsoft Word. Follow these steps.

Open your Word document.
Check (turn on) “Check grammar with spelling.”
Check (turn on) “Show readability statistics.”
Left-click “OK.”
Spell-check your document.

After the spell-check, you will see a report of “Readability Statistics.” The Flesch Reading Ease score is the second-last number in the list.

When writing for business, aim for a score above 50. If the topic limits what you can do, you may have to settle for 30 to 50. But anything below 30 is too hard to read. Many readers will give up. You will lose sales. So, dig in and start rewriting.

Readers of academic and scientific writing generally tolerate lower readability than readers of business writing. However, that doesn't necessarily mean that you should strive for a low score in academic and scientific writing. All readers appreciate high readability, often unconsciously.

The Takeaway: Get in the habit of checking your Flesch Reading Ease readability score while you check your spelling. Aim high. With continued practice, you will be able to attain high readability almost effortlessly. Your readers will notice.


  1. I don't agree that business writing demands higher readability. So much business writing is UNreadable (e.g., unedited, terrible diction, logical transitions often missing, teeming with sentence fragments and inconsistent punctuation). The kind of business writing most people external to business observe, like web copy and marketing materials, is more literate, but the writing that actually operates the business (planning documents, business requirements requests for proposal, statements of work, and so forth) are usually pretty awful. At best they're drab, sanitized and complete--which doesn't really make for great reading.

    This blog post is a really useful tip. Thanks.

  2. Thanks a lot for this precious information,
    What about writing an academic paper ? would it be better to have a high or low readability score?
    I know you have mentioned that the reader would appreciate high scores but what about the conference committee?
    thanks a lot

    1. Thank you for visiting my blog. Interesting question! Based on my experience, I would suggest doing this: Download some papers that other writers have presented at previous years of the conference where you want to present. Paste each paper into a word processor and check its Flesch Reading Ease (FRE) score. These scores will give you an estimate of the range of readability of the typical papers the committee will accept. Then, in YOUR paper, aim for an FRE at or near the TOP of that range. In other words, aim to make your paper like the more-readable, not less-readable, papers typically presented. Don’t make your FRE score HIGHER than the top of the range, lest the committee find it too informal. CAUTION: I have spent my entire career in business writing and have had little experience in the world of academic papers. Don’t rely solely on my advice; also seek advice from within your community. Thanks again for a great question. My best wishes to you.