Nothing beats having a real human check over your work before you publish it, but there are a lot of useful tools available to help eliminate common errors. If you are a serious writer, it could be worth using one (or more) of these as a way of identifying common mistakes you make. Bear in mind, though, that they aren’t really capable of accounting for tone of voice or stylistic choices.
Some of the most popular of these tools are:
Grammarly – https://app.grammarly.com
This is probably the most well-known grammar checker at present. It offers both free and paid versions.
Perfect It – https://intelligentediting.com/
Aimed more at editors, the main benefit of this is its consistency checking ability. There is a free trial available.
ProWritingAid – https://prowritingaid.com/
A comprehensive grammar and style checker, ProWritingAid offers a vast array of features, including checks for readability, consistency and overused words. There is a free online checker and paid download/plug-in.
Typely – https://editor.typely.com/
Stating right from the start that it is NOT a grammar checker, Typely analyses usage (jargon, redundancies, jargon, etc) and aims to ‘tighten’ your work. It is free to use.