What mistakes will the spellchecker not find?

The spellchecker is effective for detecting basic spelling errors. However, it fails to catch nuanced mistakes such as homophones, compound word issues, factual inaccuracies, incomplete punctuation pairs, dangling modifiers, missing words, repetitions and style inconsistencies. Authors preparing their texts for publishing should recognise the limitations of spellcheckers and consider the indispensable role of human editors in refining their manuscripts.

Spellcheckers are great tools for easy and quick fixes. But you should not depend on them as the only method of correcting your text. Since they do not consider content, style, target audience and many other elements that influence language, they have a minimal scope. They miss out on homophones, problems with compound words, factual inaccuracies and errors, incomplete punctuation pairs, dangling modifiers, repetitions, missing words and inconsistencies.

Perhaps we should leave them to do the one thing they have been designed to perform — check the spelling. However, even in this case, they sometimes underdeliver. Let me show you some most common examples of mistakes (but there are many more!) that will slip through the spellcheckers’ cracks. On the other hand, a human editor can easily diagnose.

Homophones and confusable words

Homophones are sets of words (two or more) pronounced alike but different in meaning, spelling or etymology. For instance, to/two/too, hear/here, by/buy/bye, sell/cell and so on. Because they are spelt correctly, the spellchecker cannot detect them, despite not fitting the context:

  • Leading a stationery lifestyle and following unbalanced diet may be harmful to your health. (stationary)
  • Jonathan sent his complements to the chef even though he didn’t enjoy the meal in the least. (compliments)
  • Barbers, woodpeckers, and babblers are globally threatened species of birds. (barbets)
  • The French sociologist, Martine Segalen, touched upon the unclear family in the context of individualism and freedom in her book Historical Anthropology of the Family. (nuclear)
  • The continued spread of plantations at the expanse of forests is a severe threat to biodiversity. (expense)

Issues with compound words

Compound terms may be separated with a space, hyphenated or written as one word. However, there is an increasing tendency to avoid hyphenation in noun compounds, New Hart’s Rules (3.3.3) informs. For instance, Oxford Advanced Learner’s Dictionary specifies airstream rather than air-stream and air raid rather than air-raid.

  • He noticed how beautiful her face looked in the moon light. (moonlight)
  • It has become common practice to delegate overall board tasks to board committees to ensure appropriate treatment of topics and line up of expertise and capacity. (line-up)
  • The tin foil should not be disposed in the blue wheelie bin. (tinfoil)

Factual inaccuracies

From the perspective of language correctness, cohesion and clarity, there are no issues with the two sentences below. You will need a human brain (of an editor) to cross-check the information and point out that the dates, names and other facts are incorrect.

  • The Pig War (1858) was a conflict between the United States and the United Kingdom over the border in the present-day State of Washington and Canada. (1859)
  • Tony Blair was the Prime Minister when the UK voted in the Brexit referendum in 2016. (David Cameron)

Punctuation ‘pairs’

In some cases, punctuation marks do not like to be alone. When introducing one comma, hyphen, bracket or quotation mark, inevitably, you need to use its closing counterpart. These ‘pairs’ are not detectable by spellcheckers, and, as an editor, I routinely correct them.

  • After the meeting, he said, ‘I’m going to work late, so I left the office alone. (The closing quotation mark is missing.)
  • After the meeting, he went back to work — where he spent the entire afternoon so I left the office alone. (The closing em rule is missing.)

Dangling modifiers

Dangling modifiers are common grammatical errors where the modifying word or phrase attaches to the wrong subject or where the subject is missing in a sentence. Correcting dangling modifiers usually requires rewording the sentence. Let’s consider the following examples:

  • ‘Driving through the countryside, the smell of fresh air was overpowering.’ The subject to be modified by the participial phrase is missing in this sentence. Introducing the subject and amending the modifier can correct this sentence: ‘Driving through the countryside, they encountered the overpowering smell of fresh.’
  • ‘I was upset with my sister when she returned the car scratched with bad attitude.’ Here ‘with a bad attitude’ functions as a dangling modifier because it is too far from the intended subject (‘my sister’). As a result, it instead appears to modify the ‘car,’ which did not have a bad attitude.

Missing words

Take the following sentence: ‘My dress ruined by the wine stain.’ A word is missing, but the spellchecker will not highlight an issue. Similarly, as an author (too) familiar with the text, you might not be able to spot it, in which case an editor can help.


Writers often instinctively use their core vocabulary; meaning — words repeat in the same sentence, paragraph or globally in the manuscript. A spellchecker will not see an issue with repetitions, while an editor will look at the text from a bird’s eye view. You can also turn to writing assistants or dictionaries to find suitable synonyms.

Style inconsistencies

There are so many inconsistencies that require an eye of an editor to lead your fiction into a publishable form. The spellchecker will not find inconsistencies such as the following examples:

  • In the first chapter, one of the tertiary characters is bald, but in the epilogue, he was getting a cut to tame his long locks?
  • Was he called Dave initially, but he became a Dan in the middle of the book?
  • Chapter three comes immediately after chapter one?

Inconsistencies, albeit of a different kind, also occur in professional, academic or any other nonfiction texts. For instance, they could involve using:

  • more than one referencing system,
  • various (correct) spellings of the same word. For instance, ‘urbanize’ is in use in UK English alongside ‘urbanise,’ according to the New Oxford Dictionary for Writers & Editors. A spellchecker will not pick up such discrepancies, but an editor will.

When the spellchecker is not enough, how can professional editing help?

Professional copyediting and proofreading play a crucial role in refining a text for publication. While spellcheckers are useful, they cannot replace the human eye and mind when identifying and correcting issues with homophones, compound words, factual inaccuracies, incomplete punctuation pairs, dangling modifiers, missing words, repetitions and style inconsistencies. Professional copyediting and proofreading can help ensure that the text is free of errors, flows smoothly and adheres to the appropriate style and tone for the target audience. They can also provide constructive feedback on areas needing improvement, such as clarity, coherence and organisation. Overall, professional copyediting and proofreading can help elevate a text to its highest potential and increase its chances of success in the publishing world.


Spellcheckers detect basic mistakes. However, you should never rely upon them as the only tool when editing a text. Eventually, you will need the help of an editor to bring your manuscript to a publishable version.

I am an experienced editor, working with non-fiction, academic and business books. If you need proofreading and editing of your story, contact me for a free sample edit (and remember to use my early bird discount). You can also follow me on MastodonTwitter and LinkedIn for more editing tips for writers or sign up for my newsletter.

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I am an editor, indexer and a lifelong lover of literature with a PhD in literary history. I am an Intermediate Member of the Chartered Institute of Editing and Proofreading, a student member of the Society of Indexers and a vetted partner of the Alliance of Independent Authors.