An AI writing assistant is a program that uses a language model to help you write. It drafts from your notes, rewrites what you already have, or checks it for mistakes, and most do some of all three. There are four kinds: checkers that work on your text where you type it, general chat assistants, tools built for one sort of writing such as novels or marketing, and assistants built for everyday messages. Pick by the writing you do most, then try it on one real piece of your own before you decide.
What an AI writing assistant does
Every one of them does some mix of three jobs.
- Drafting. You say what you want and it writes it: an email from three notes, a speech from a list of memories.
- Rewriting. You give it your text and it makes it shorter, clearer, friendlier or firmer.
- Checking. It finds the spelling, grammar and punctuation mistakes and fixes them.
Each product leans towards one of the three. Knowing which one you need most is half of choosing.
The four kinds
| Kind | What it is | Good for | Watch out for |
|---|---|---|---|
| Checkers and rewriters | Sit inside your browser and apps and mark up what you wrote | Catching mistakes and tightening your own text | They polish a draft. They do not know what you meant to say |
| General assistants | A chat window you can ask for anything | Drafts, outlines, questions, many jobs in one place | The answer often needs editing before it sounds like you |
| Specialist tools | Built around one kind of writing | Long projects with their own structure: a novel, a campaign | More to learn, and narrow by design |
| Message writers | Built for emails, texts and replies to real people | The writing you do every day | Not made for research or code |
Some names, with what their own sites say:
- Grammarly calls what it does AI writing assistance. It works in desktop apps, browser extensions and on phones, checks grammar, shows the tone of what you wrote, and rewrites sentences.
- ChatGPT, Claude and Gemini are general assistants. Claude's site lists first drafts and editing among many kinds of work, and Gemini's lists help with researching and writing.
- Sudowrite says it is built for fiction, with novelists in mind, and that it takes a writer from idea to outline to chapters.
- Jasper says it is built for marketing teams, and that it keeps a brand's voice the same across articles, emails, ads and social posts.
This page does not rank them. The best AI for writing gives our own test results by job and says which tools we did not test.
What they are all bad at
Whichever kind you choose, the same weaknesses come with it.
- Facts. A model will add a date, a name or a reason you never gave it, because the text feels more complete that way. It also states things that are false in the same calm voice as things that are true.
- Knowing your reader. It does not know that your boss hates long emails or that your sister is still cross about June. Unless you say so, it writes to nobody in particular.
- The average answer. Give it little and you get the most common version of the thing: the cover letter everyone sends, the toast everyone has heard.
- Long pieces. Over many pages it repeats itself, loses track of what it said earlier, and settles into one rhythm.
- Judgement. Ask whether your draft is good and it will usually say yes.
None of them should be trusted with a medical, legal or money decision. Check those with a real source or a real person.
How to pick one
- Name the writing you do most. Replies and emails, reports, essays, fiction, posts for a business. One assistant rarely suits all of them.
- Decide where it should live. If you want mistakes caught in every text box as you type, you want a checker. If you want a draft written for you, a separate chat window is fine.
- Read what happens to your text. Look at the privacy page. Are your chats kept? Are they used to train the model? Can you delete them?
- Test it on something real. Take a message you actually need to send today. Give two assistants the same notes and see which draft needs less changing.
- Look at the shape of the answer. One version you can use, or three options with a paragraph of notes around them? The second costs you time every day.
- Try it free first. Many have a free tier or a trial. Use it on a full week of your real writing before paying.
How to get a good draft from any of them
The assistant matters less than what you give it. Say who the text is for, what happened, what you want, how long it should be and what to leave out.
Write a reply to my neighbour, Mrs Okafor. She has asked us to cut back the hedge on her side by Saturday. I can't do it this weekend, but I can do it the weekend after. Friendly, under 80 words, the way I'd say it over the fence. Only the message.
That takes half a minute to type and saves three rounds of corrections. There are more like it in AI writing prompts. Then read the draft before it goes anywhere, and change whatever you would not say.
Where Hemmingway fits, and where it does not
Hemmingway is the fourth kind. Its model, Hemmingway-1, was built for writing to people: emails, texts, replies, letters, speeches and short stories. It gives you the text you asked for, one version, without a menu of options.
In our own blind tests it came first for everyday writing, level with Fable 5.1, and first for sounding like a person. Those two tests are ours, and the method and scores are on the model card. In the app you can tell it who people are, in People, and keep a Memory of facts it should know, which you can read, change or delete line by line. The apps for Mac, Windows and Android also have an Inbox that drafts your replies for you to read and send.
Where it does not fit:
- It is not a checker. It will not underline your typos as you type in another app.
- It is not a general assistant. It is built for writing, not for code or research.
- For long fiction, larger story models scored higher in our own story test.
- It is English-first.
If you want to try one job without setting anything up, the free tools each do a single thing: the AI email writer drafts an email from your notes, and the AI grammar checker fixes a passage you paste in. There is a free trial with no card needed. Plans are on the pricing page.
Try HemmingwayDownload the app
Common questions
What is an AI writing assistant?
It is a program that uses a language model to help you write. It can draft text from your notes, rewrite what you have, or check it for mistakes. Some work inside your browser and apps, and some are a separate chat window.
What is the best AI writing assistant?
It depends on the job. A checker suits people who write their own words and want them clean, a general assistant suits mixed work, and a specialist tool suits a novel or a marketing team. In our own blind tests Hemmingway-1 came first for everyday messages and for sounding like a person, and larger story models scored higher for fiction.
Is there a free AI writing assistant?
Many have a free tier or a trial, and their own sites say what it covers. Hemmingway has a free trial with no card needed, and its free tools open that trial with your answers filled in.
Can an AI writing assistant write in my voice?
It can get close if you show it how you write. Paste a few messages you have sent, say who the new one is for, and ask it to match them. How to make AI write like you goes through it step by step.
Is it cheating to use an AI writing assistant?
For your own emails, messages and letters, no more than using a spellchecker or asking a friend to read a draft. For school, a job application test or anything that asks for your own words, check the rules first and follow them.
Is my writing private when I use an AI writing assistant?
That depends on the product, so read its privacy page before you paste in anything sensitive. Hemmingway never trains its models on your chats, memory or People, and its privacy page lists everything that is kept.