Your brain is helping, and that is the problem
Reading is not letter by letter. Your brain predicts what should be there from shape, context and habit, then checks loosely against the page. Efficient, and completely unhelpful when you are hunting mistakes.
The effect is strongest on your own writing, because you already know what the sentence was supposed to say. You are not really reading it. You are recognising it.
Which is why the error is so often in the headline, the button label or the first line. Big text gets skimmed harder than body text, and those are exactly the words you looked at most while writing.
Technique one: hear it
The single most effective change is to stop reading and start listening.
A speech synthesiser has no idea what you meant. It reads what is actually there, at a fixed pace, without skipping. A missing word becomes a gap you hear. A repeated "the the" stops sounding invisible. A sentence you thought was fine turns out to need three breaths.
Clumsy rhythm shows up too, which reading silently hides. If a sentence sounds like it is running out of air, it is too long, whatever the grammar checker thinks.
Paste the text into text to speech and follow along on the page while it reads. Following along matters: hearing alone lets you drift, and the point is to force your eyes onto the words your ears are receiving.
One warning. Synthesised voices mispronounce names, acronyms and technical terms constantly. Ignore those. You are listening for gaps and stumbles, not diction.
Technique two: break the shape
Anything that makes the text look unfamiliar restarts the part of your brain that reads properly.
Change the font. Serif to sans, or into something you never write in. Change the size. Change the background colour. Print it, if the piece matters enough.
Read it backwards, sentence by sentence from the end. Meaning stops carrying you along, so each sentence has to stand by itself.
Sleep on it. A day is worth more than an hour, and an hour is worth more than reading it four times in a row, which is worth almost nothing.
Technique three: diff the versions
This one applies whenever the text has been through someone else's hands, and it catches a category of problem no amount of rereading will.
You send a draft. It comes back edited. Somewhere in those changes is a paragraph that got dropped, a figure that got altered, or a hedge that quietly became a promise. Rereading will not surface it, because you will simply read the new version and find it fine.
Comparing the two versions side by side shows you every change, including the ones nobody mentioned. Text compare will do that on two blocks of text without needing either to be a file.
Where I use it most: legal wording that came back from review, translated copy against the original, and a page after a CMS migration. Migrations are the worst offender. Smart quotes turn into question marks, accented characters break, and the only reliable way to find it is a machine comparing old against new.
Technique four: check the things a human cannot count
Some errors are not really errors. They are patterns, and patterns are invisible when you are inside them.
Sentence length is the main one. If every sentence runs to twenty-five words, the writing is exhausting no matter how correct it is. The plain language guidelines published by the US government are blunt about this, and they are worth reading even if you write nothing official: short sentences, active voice, and the point before the caveat.
A readability check puts a number on that. Do not chase the number, and do not write to hit a grade level. Use it the way you would use a bathroom scale, as a signal that something drifted.
Word count matters when a limit exists and nowhere else. A meta description that overruns gets cut mid-sentence by Google. A university essay over the limit loses marks before anyone reads it. The word counter is for the cases where a hard number is real.
Clean the invisible stuff before you publish
Text copied out of Word, Google Docs, a PDF or an email carries passengers.
Curly quotes that break in code blocks. Non-breaking spaces that stop lines wrapping properly on phones. Zero-width characters that make a search for a word fail for no visible reason. Line breaks in the middle of sentences, courtesy of a PDF's column layout.
None of this is visible on screen. All of it shows up later, usually on someone else's device, usually after publication.
Running the text through a cleaner before it goes into a CMS takes seconds and removes a category of bug that is genuinely hard to diagnose after the fact.
The order I actually use
Write. Leave it. Clean the hidden characters. Listen to it while following the words. Fix what you heard. Check the length figures if a limit applies. Diff it against the previous version if there was one.
Ten minutes, most of it not reading.
And the thing none of this fixes
A spellchecker cannot tell you that "manager" should have been "managing director", that the price is out of date, or that the paragraph contradicts the one above it. Neither can a readability score, and neither can I.
For anything with consequences, a second person still beats every technique on this page. These methods are for catching the mechanical failures so that the human reading it can spend their attention on the ones that matter.
Questions people ask
Because you are recognising the text rather than reading it. Your brain predicts each word from context and shape, and since you already know what the sentence should say, the prediction wins over what is actually on the page. Anything that makes the text unfamiliar, such as a different font or hearing it aloud, breaks that shortcut.
Yes, and having a machine read it to you works better than reading it yourself, because a synthesiser has no idea what you meant. It cannot silently repair a missing word the way your own voice will. Follow the text on screen while it reads, otherwise your attention drifts.
Compare them rather than reread them. A diff shows every change, including the ones nobody flagged in the email. This matters most for edited legal wording, translations against an original, and content moved between systems, where quotes and accented characters break silently.
Do not aim for one. Use it as a drift signal rather than a target, because writing to hit a grade level produces text that scores well and reads badly. If the number jumps between drafts, look at your sentence lengths. The plain language guidelines are more useful than any single score.