AI Writing & Rewriting
We tested and ranked 58 AI Writing & Rewriting apps for Mac — updated August 2026.
Every app here was run on our own Apple-silicon Macs and scored on the published rubric — capability, craft, privacy, value. We watch the network while we test. How we rank →
You have a draft that needs tightening — an email that rambles, a paragraph that buries its point, a message whose tone lands wrong. The usual fix is pasting it into a cloud service, but that sends your words to someone else's server before they come back polished. AI Writing & Rewriting apps on Mac take a different approach: they proofread, rewrite, change tone, expand, or shorten your text right on your device, so your drafts stay private and any network calls happen only when you explicitly opt in.
We evaluated 58 apps in this category, scoring each on capability, craft, privacy, and value. The field ranges from system-wide hotkey polishers and AI keyboards to full writing studios running open-source LLMs offline. Some rely on Apple Intelligence, others let you load your own models via Ollama or direct LLM integration, and a handful offer optional cloud keys for heavier tasks. Below is our ranked list, starting with the apps that best combine useful writing help with genuine on-device privacy.
The ranking — all 58
Rytability
Rytech Labs, LLCA rare writing assistant built specifically for dyslexic writers — it fixes spelling, homophones, and sentence structure without steamrolling your voice, running 100% on-device AI with no data collection.
” runs entirely on your device with 100% local AI processing. No internet required. No cloud uploads — test note
Clean Text
Ivan GobboA mature text-cleanup utility with over 100 formatting transformations and a 4.6-star track record across 201 ratings, layering Apple Writing Tools on top so you can rewrite, summarize, or proofread on-device when you choose.
” supports Apple Writing Tools... use them to correct, rewrite, summarize, and improve your text directly in the app — test note
TextMaster AI Keyboard
Weiliang WangA system keyboard that rewrites, proofreads, adjusts tone, and translates inside any app without copy-paste — though its AI defaults to cloud, with on-device processing available only when you toggle Private Mode on.
” In Private Mode, the AI works offline on your device, so your text is never sent anywhere — test note
LudyType - AI Keyboard
Ludy Ankas, LLCAn all-in-one AI keyboard that packs grammar and spelling fixes, rewrites, summaries, translation, text snippets, clipboard management, and voice input into a single system keyboard you use across every app.
” All processing is fast, private, and designed to make your writing better — test note
IWL: Smarter Writing
Koding Robots dooStands apart by performing real on-device linguistic analysis — style fingerprinting, NLP-powered word statistics, sentence ranking, readability scoring — instead of piping text to a cloud LLM. Optional AI editing uses your own API key and stays clearly separate.
” Offline-friendly: tools work without internet. Your words stay yours; custom English linguistic fingerprinting model; NLP model to parse text — test note
Instarep.ly
Cody Russell BontecouA clean on-device keyboard that drafts context-aware replies from copied text using Apple Intelligence, with no backend server or account required. Tone profiles for work, family, and brand voice let you keep a consistent style across apps.
” generate a reply locally with Apple Intelligence; Reply generation happens on device; No accounts, backend AI service, or remote reply generation — test note
Mutus – Private Note Cleaner
Jean DegeorgeA focused note-cleanup tool that takes raw notes, reformats them with a selectable local LLM, and offers a clinical SOAP mode for healthcare professionals — with nothing ever sent off-device.
” cleans up and formats your notes fully privately using local AI; At no point are your notes sent to the internet — test note
Write Lint
Hexaget, IncA system-wide hotkey text polisher built on Apple's on-device Foundation Models that fixes typos and punctuation with a sub-second word-level diff in any app, preserving your voice rather than rewriting wholesale. Free and fully offline.
” built on Apple's on-device Foundation Models; no network calls for text processing. It works on a plane — test note
Manzoni: Local AI Writing App
Gems Platforms, Inc.A privacy-first Mac word processor that runs fine-tuned open-source LLMs entirely offline, with an inline prompt bar and select-to-edit built directly into the writing surface — no cloud round-trip involved.
” It runs fully on your machine — test note
LocPilot for Word
PatentLM LLCA Microsoft Word add-in that runs your own local LLMs right inside your documents, keeping everything fully offline in a writing category where most competitors require a cloud connection to function.
” runs entirely on your computer; work offline without any internet connection; run your favorite local LLMs right inside Microsoft Word; no cloud — test note
How to choose AI Writing & Rewriting for Mac
Start with where you write. If you work across many apps — email, Slack, notes — a system keyboard or global-hotkey tool saves you from copy-paste loops. If most of your time goes into one editor, a dedicated writing app with inline AI or a Word add-in keeps everything in context.
Next, consider how much AI muscle you need. Light-touch fixers that correct typos, punctuation, and minor grammar run fast on Apple's on-device Foundation Models with no setup. Deeper rewriting — tone shifts, expansion, summarization — benefits from a larger model, which usually means open-source LLMs running locally through the app or via an Ollama-style server you configure yourself.
Privacy architecture matters more here than in most categories, because you are handing over your actual writing. Look for apps where on-device is the default, not an opt-in toggle buried in settings. Several entries on this list are cloud-first with a local fallback, which is a meaningfully different posture from local-first with an optional cloud upgrade.
Finally, price. Many of the strongest picks are free or cost a one-time fee under ten dollars. Subscription models exist but are harder to justify for a tool that handles one editing action at a time.
Questions people ask
Can a local AI writing assistant on Mac replace Grammarly?
The apps in this list handle core Grammarly jobs — spelling, grammar, punctuation, tone adjustments — without sending your text to the cloud. Several work system-wide via hotkey or keyboard extension, so the workflow feels similar. Where they differ is depth: cloud services train on larger datasets and catch subtler style issues, while local tools trade that edge for privacy and offline access. For everyday proofreading and rewrites, a local app is a practical alternative.
Do these AI writing tools work offline on a Mac?
Most of the top-ranked apps process text entirely on-device and function without an internet connection. Apps built on Apple's Foundation Models run offline on compatible hardware out of the box. Those running open-source LLMs work offline once you download the model files. A few entries are hybrid — they default to cloud processing but offer a local mode you can switch on. Each review below notes whether the app is local-first or cloud-first.
What Mac hardware do I need for a local AI writing assistant?
It depends on the approach. Apps powered by Apple Intelligence require Apple Silicon and enough RAM to run Foundation Models. Apps that load open-source LLMs locally recommend at least 8 GB of unified memory, with 16 GB or more for larger models that produce better output. Lightweight tools that only fix spelling and punctuation have minimal requirements. Each listing notes specific hardware needs where the developer states them.