How smartphone autocorrect works and how to customize it

There automatic correction (or text replacement) is an extremely useful function in our smartphones, which in case of spelling or typing errors replaces misspelled words with correct ones. This function, now widely used on both Android smartphones and iPhones but also in various applications for Windows and MacOS such as Excel, was invented in the 1990s by the engineer Dean Hachamovitch of Microsoft who, working on the Word developmenthad an intuition: use the program's glossary to automatically correct the most frequent typing errors.

What is autocorrect and how does it work

The automatic correction function corrects words typed with spelling errors by replacing them automatically and in real time with the correct words reported in a reference dictionary. To invoke this functionality, just write in a text field and, if it has not been previously deactivated, the automatic correction should come into action where appropriate. The conditional is a must because the automatic correction is not always able to work appropriately: sometimes it does not correct some errors, sometimes it does so incorrectly or inappropriately. In general, however, automatic correction works quite well and is undoubtedly useful.

But how does autocorrect understand when and how to correct text? In short, it does so through the combination of text recognition algorithms which compare the words entered by the user with those of a dictionary used as a “reference”. For the most common typos, these algorithms also use a default list of overrides. For example, “bnee” is automatically corrected to “well”.

The most advanced and modern automatic correction systems, such as those present on our smartphones, are also able to learn writing habits and improve over time to avoid correcting false positives and learning technical or slang words that would otherwise be reported as errors.

How to turn autocorrect on and off

Based on your usage needs, you can activate and deactivate the automatic correction function using your smartphone settings.


The procedure to follow above Android may vary depending on the version of Google's mobile operating system you are using. In the specific case of the device available in the editorial office that we used for the relevant tests, this was made possible by going to Settings > Additional settings > Language & input > Spell check and moving up Hon the switch located next to the item Turn on Spell Checker or up OFF to deactivate the function.

On other devices the steps and wording may be slightly different, so it is best to refer to the official instructions provided by your manufacturer.


On iPhonehowever, to activate or deactivate spell checking, you need to go to Settings > General > Keyboard and use the switch ON/OFF located next to the entry Automatic correction to enable or disable the function in question.

From the screen Keyboards it is also possible to act on the switches relating to some “collateral” options relating to the automatic corrector, including Automatic capitalization, Predictive text, Check spelling, Caps Lock, Smart punctuation And Abbreviation “.”.

How to manage the autocorrect function and customize it

The automatic correction function can be managed and personalized to better match your specific needs and to do this you usually need to act from the keyboard settings (in the case of Android) or in the system settings (in the case of iPhone).

With regard to Androidonce you arrive in the section Settings > Additional settings > Language & input > Spell check (or in the corresponding section available on your smartphone), you need to tap the item Manage keyboardsthen select the wording Settings attached to the current keyboard and, from here, it is possible to act on the functions of text correction available for the keyboard you are using.

On iPhoneinstead, you have to go to Settings > General > Keyboard > Text Replacementtap the button + (top right) and create the abbreviation that will automatically write a certain word or phrase using the appropriate function.

Furthermore, regardless of the keyboard and mobile platform in use, in many cases it is possible to add terms to the dictionary or select the word with which to correct an error by touching the word reported by the automatic corrector and deciding to add it to the dictionary or replace it with a correct term from those listeddepending on the circumstances.