monthletThink. Speak. Done.
The note app where AI writes the note — layout and all. Just speak your mind.
Free · macOS (Apple Silicon) · Windows
From a messy brain-dump to a structured note.
You use AI every day. But your workflow still looks like this:
Ask AI
That's not a workflow. That's busywork.
monthlet is different. Three steps, and the AI does the hard one.
Think
Dump your raw thoughts: bullet points, fragments, half-formed ideas. No structure needed.
Speak
Tell monthlet what you want. “Turn this into a note.” Plain language.
Done
AI writes it, choosing banners, columns, tabs automatically. Need changes? Just ask, and only that part updates.
From messy text to a finished note, in one sentence.
Watch monthlet turn a brain-dump into a structured note, then refine it by just asking.
45-second demo, real time.
Not just notes. A whole document, talked into shape.
📊 Spreadsheets
Build and edit real spreadsheets by talking: formulas, formatting, the works.
📈 Live charts
Charts that bind to your sheet data and update as the numbers change.
🎨 Instant themes
Restyle an entire note in one request. No CSS, no fiddling.
📅 Calendar
Browse your notes by month, week, or day. Each day’s daily note is one click away. Write a time on the same line as a date, like 13:00–14:00, and the note shows up at that time.
🗺️ Note map
See how your notes link to each other — and which ones nothing points to.
🏷️ Tags
Tag a note in a word, then filter the gallery down to just those notes.
📋 Templates
Meeting notes and Weekly review come with the app. Ask for one in the chat and its structure becomes the base, while the content is written for what you asked.
🔗 Links in chat
Ask which notes nothing points to, or what sits near a particular note. Ask for links to be added and they are written with paths that work from the note being edited.
📐 Diagrams
Flowcharts, org charts and mind maps, drawn from what you describe. The layout is worked out for you, so there is no dragging boxes around.
🔌 Connectors
Works with Google Sheets and Google Calendar. Any MCP server can be connected too.
📄 PDFs
Drop a PDF into a note and its first page shows up in the body. Click it to open the file, so receipts and bookings stay where you can see them.
🗂️ Kanban boards
Put a kanban board in a note and drag cards between columns. Link it to a spreadsheet and each row becomes a card; moving a card changes the status column in the sheet.
✅ Tasks and due dates
Give a checklist item a due date. The task list gathers them from every note into Overdue, Today, Next 7 days, Later and No due date, and dated tasks also show on the calendar.
⚡ Quick capture
Press Control+Shift+Space in any app to jot something down. It is saved as a new note, or added to the end of today’s daily note.
Your notes. Forever.
monthlet = anagram of <html> + note
That's not a pun. It's the whole philosophy. Every note you make is a plain HTML file on your machine. Open it in any browser, today or in ten years.
💾 Local-first
Your notes live on your disk, not our cloud. With your own key, your data never has to touch our servers.
🔓 No lock-in
Plain HTML, readable by anything. You're never trapped.
♾️ Outlives us
If monthlet disappears tomorrow, your notes still open. Forever.
Bring your notes in. Take them back out.
Start with the notes you already have. Importing runs on your computer and doesn't call AI, so it uses no API tokens.
📥 Markdown and Obsidian folders
Import one file or a whole folder. Folder structure, [[wiki links]], Markdown links, images, callouts, highlights, footnotes and frontmatter come across.
📊 Spreadsheets
Import Excel, CSV and TSV files as spreadsheets, or bring in a Google Sheet through the connector. Value filters and data validation (drop-down lists, number and date rules) in Excel files carry over on import and export.
🔁 Markdown round-trip and Word export
Export any note to Markdown. Frontmatter keys monthlet doesn't use are kept, so a note round-trips without losing its metadata. Notes can also be exported to Word (.docx), with headings, lists, tables and text formatting you can edit; charts and diagrams go in as images.
The app is free. AI without a key is a service.
The app, free and complete.
- Unlimited notes
- Full AI with your own API key
- Claude, ChatGPT, Gemini, or any OpenAI-compatible endpoint
- Local-first: your notes stay yours, forever
Don't want to manage an API key? Subscribe and monthlet runs the AI for you. No key, no setup. Everything else in the app stays exactly the same.
Questions, answered.
Do I need an API key?
Yes, bring your own (Claude, OpenAI, Gemini, or any service with an OpenAI-compatible API). Your data never touches our servers. Prefer not to manage a key? monthlet AI (coming soon) runs it for you.
Which AI providers are supported?
Claude, ChatGPT, and Gemini are built in. You can also connect any service that exposes an OpenAI-compatible API (DeepSeek, OpenRouter, a local LLM server, and so on) by entering its endpoint URL, key, and model name; how well it works depends on the model behind the endpoint. Set up whichever key you already have during onboarding, and switch anytime in settings.
In Help: Provider settings (API keys, BYOK, connection test)
Is my data sent to monthlet's servers?
Never, when you use your own key. Notes stay on your machine; AI requests go straight from your device to your chosen provider.
Is there a note limit?
No. Notes are always unlimited.
What's monthlet AI?
monthlet is free with your own API key. monthlet AI is a subscription that runs the AI for you: no key, no setup. The app itself stays exactly the same. Coming soon. Join the waitlist.
Does it work offline?
Read and directly edit existing notes offline. AI features need a connection.
What if monthlet shuts down?
Your notes are plain HTML files on your machine. They open in any browser, forever.
Which platforms?
macOS on Apple Silicon (M1 or later) and Windows. The Windows version is on the Microsoft Store.
Can I use my notes on more than one machine?
Yes. A vault is just a folder, so keeping it in iCloud Drive, Google Drive, or Dropbox syncs it. Notes download as you open them, and if the same note was edited in two places monthlet asks which version to keep.
In Help: Following changes from outside the app (cloud sync, other apps)
Can monthlet work with PDFs?
Yes. Drop a PDF into a note and its first page is added as an image; click the image to open the file. The AI can also read PDFs in your vault when you name one — for example, “Read receipt.pdf and tell me the amount and date.” Scans without a text layer cannot be read this way.
In Help: File attachments (add images, PDFs, etc. to a note)
Can I sort and filter a spreadsheet?
Yes. A column's filter menu keeps rows by value or by condition (greater than, between, contains text, empty, and more), and you can search its list of values. To sort part of a sheet, or by more than one column, select the cells, right-click and choose "Sort range…". When you copy and paste a formula, its relative references shift to where you paste it; references with $ stay fixed.
Can monthlet use my other tools?
Yes. Register any MCP server and Chat can use it; anything that writes asks for confirmation first. Google Sheets and Google Calendar are built in: give Chat a spreadsheet URL and it reads the contents, and it can read your schedule and add an event when you ask for one. Spreadsheets are read-only, and every calendar event is shown to you for approval before it is created. The other direction works too — see below.
In Help: Connectors (external integrations)
Can I use my notes from Claude Code?
Yes. monthlet can act as an MCP server, so an agent outside the app reads your notes through monthlet instead of editing the files behind its back. Turn on Publish to external agents in settings (off by default) and run the setup command it shows you. Reading only to begin with; writing is a separate switch. Moving and renaming are allowed with a separate switch, and so is deleting (off by default); deleted items go to your system's trash. The previous version of a rewritten note stays in its change history, and agents connect only from your own machine, only while the app is running.
Can I go back to an earlier version of a note?
Yes. monthlet keeps a change history per note, so you can look at an earlier version and restore it.
Ready to stop formatting and start thinking?
Free · macOS (Apple Silicon) · Windows