Jasper and Hemmingway both use AI to write, but they are built for different jobs. Jasper is an AI content platform for marketing teams: blog posts, ads, product copy and campaigns, kept in a company's brand voice. Hemmingway writes the messages a person sends: the email to a client, the text to a landlord, the reply you have been putting off, in your own voice rather than a brand's.
So the choice is mostly about the job. If you are producing marketing content for a company, with a team, a brand and a campaign calendar, Jasper is built for that and Hemmingway is not. If you want help with your own emails, messages and everyday writing, Hemmingway is built for that and Jasper is not the obvious fit. We have not tested Jasper, so this page compares what each is for, not which writes better.
The short version
| Hemmingway | Jasper | |
|---|---|---|
| Built for | Personal messages and everyday writing | Marketing content for businesses |
| Whose voice | Yours, to each person you write to | Your company's brand |
| Typical output | An email, a text, a reply, a letter | Blog posts, ads, campaign and product copy |
| Typical user | One person, at work or at home | Marketing teams |
| Drafts replies from your inbox | Yes, in the apps | Not what it is built around |
| Tested by us | Yes | No |
Two kinds of voice
Both products talk about "voice", but they mean different things.
A brand voice belongs to a company. It is the way the company sounds everywhere: on the website, in ads, in the newsletter. It has to stay the same whoever on the team is writing, and whether the piece is a headline or a thousand-word post. Keeping that consistent across many writers is a real problem for marketing teams, and it is the problem Jasper is built around.
Your own voice belongs to you, and it changes with the reader. You write to your boss one way and to your sister another. A two-line text to a friend and a careful email to a client should not sound like the same document. That is what Hemmingway is built around. In Hemmingway, People holds who each person is to you and how you write to them, in the language you use with them. Memory holds the facts it should keep in mind, and you can read, change or delete every line.
A brand voice is meant to sound the same to everyone. Your own voice is meant to sound like you to each person. A tool built for one is not automatically good at the other.
What each is good for
Jasper
Jasper suits a marketing team that needs a steady flow of content: posts, ads, landing page copy, product descriptions, social posts for a campaign. The value is in doing that at volume, together, and on brand.
Hemmingway
Hemmingway suits the writing one person does between everything else:
- the reply to a client that has sat in your inbox for three days
- declining an invitation without sounding cold
- chasing an invoice politely
- a message to someone you have fallen out of touch with
- a card, a toast, a short letter
You say who it is for and what you want said, and it gives you the message: one version, with no preamble and no list of options to cut. In the Mac, Windows and Android apps, Inbox also reads your mail and chats (Gmail, Outlook, WhatsApp, Slack and Teams, and iMessage on the Mac) and drafts each reply for you to send. How that works.
How good Hemmingway-1 is at this
Hemmingway-1 is our own 27B model. We tested it on eighty real email and message requests, in blind head-to-head matchups against some of the largest models there are, run in both orders so position could not sway the judge. It came first on everyday writing (1026) and first on sounding like a person (1032), twenty-six points ahead of the next model on the second. These are our own benchmarks, CommunicationBench and Human-Likeness, and the method is on the model card.
Jasper was not in those tests, so they say nothing about how the two compare.
It also has limits. It is English-first, it can be wrong and still sound sure, and it should not be trusted with medical, legal or money decisions.
Try HemmingwayDownload the app
Can you use Hemmingway for marketing?
For small pieces, yes. It writes short, plain copy that sounds like a person: a product update email to customers, a post announcing something, a reply to a review. But it is not built as a marketing platform, and it is not built for a team planning campaigns together. If marketing content is your main job, a platform built for marketing teams will serve you better.
If you are a founder or freelancer who writes your own announcements, try this. Give it the facts and a sample of how you write:
"Write a short email to our customers. We've added dark mode to the app. It's in the latest version. Here's an email I wrote them last month: [paste it]. Match that tone. Only use these facts. Just the email."
The sample does most of the work. The model copies what it sees far better than what it is told. More on getting an AI to write like you.
Can you use Jasper for personal messages?
You could ask it to, but it is not what it is built around. A marketing platform assumes a brand, an audience and a piece of content. A text to your landlord has none of those: it has one reader, a few facts and a tone that fits the two of you. That is the gap Hemmingway was made for.
Privacy
We never train our models on your chats, memory or People. On the web and on Android you can keep chats only on your device. Our privacy page lists everything we keep. For Jasper, read its own policies for your account.
Open weights
Hemmingway-1 is open weights under Apache-2.0, including commercial use, with a 262,144-token context. You can download it from Hugging Face and run it yourself, or call it through an OpenAI-compatible API as hemmingway-27b. That matters if you want to build your own writing tool rather than use someone else's: see the docs and the API platform.
How to choose
- Write down the last five things you wished an AI had written for you.
- Mark each one "company" or "me". A blog post, an ad or a product page is company. An email, a text or a reply is me.
- If most are company, and you work with a team on them, look at a marketing platform like Jasper.
- If most are me, try Hemmingway on those five. It is free to try, with no card needed. For plans, see pricing.
- If it is a real mix, there is nothing wrong with using both: one for the content your company publishes, one for the messages you send.
Common questions
Is Hemmingway an alternative to Jasper?
Only partly, because they do different jobs. Jasper is built for marketing teams producing brand content. Hemmingway is built for personal messages, emails and everyday writing in your own voice, and it can draft replies from your inbox.
Which is better for writing emails?
For your own emails, replies and messages, Hemmingway is built for exactly that, and Hemmingway-1 came first on everyday writing in our own benchmark. We did not test Jasper, so we cannot score it. For marketing emails sent to a whole list as part of a campaign, a marketing platform is the more natural fit.
Can Hemmingway write in a brand voice?
It can follow a tone if you give it samples, which suits short pieces such as a customer email or an announcement. It is not built for managing a brand voice across a team. If that is what you need, use a platform built for it.
Does Hemmingway train on what I write?
No. We never train our models on your chats, memory or People. The privacy page lists everything we keep.