Own your file.
Where your data lives: local files, privacy and backups
In a file that opens in your browser, where exactly is your data kept, when can it be lost and how do you back it up? Honest answers for phones, two devices and work laptops.
“Where is my data?” is the first question to ask before trusting an app. With most services the answer is short and a little vague: “on our servers, safe”. With a single file that opens in your browser the answer is more concrete: on your computer, in exactly this place. This post covers that place, when the data can be lost and how to protect it. Without making it sound simpler than it is.
Where does a file in your browser save its data?
When you open a Productive Ant kit, what you type is saved in that browser’s own storage on your computer. That storage sits on your disk, inside the browser’s folders.
That has three consequences:
- It does not go to the internet. The file connects to no server. The number, note or name you type does not leave your computer.
- It is tied to the browser and the device. If you opened the file in Chrome and typed into it, it starts empty in Safari. Same on another computer.
- It is deleted under your control. The browser’s “clear site data” option clears this storage too.
For privacy, that is a guarantee built on structure rather than on a clause in a policy. There is no server, so there is no server to leak. The money side of the same idea is in net worth without linking your bank.
When can your data be lost?
To be honest: local data can be lost too. These are the cases to know:
| Situation | What happens | What to do |
|---|---|---|
| Clearing “cookies and site data” | Your entries are deleted | Back up first |
| Uninstalling and reinstalling the browser | Usually deleted | Back up first |
| Opening it in a private window | Gone when the window closes | Use the kit in a normal window |
| The computer dies | Gone with the disk | Keep the backup somewhere else |
| Moving the file to another folder | Some browsers treat it as a new address | Back up, move, then load the backup |
Every row in that table has the same answer: a backup.
How to back up and restore
Every kit has a one-click backup button. Click it and all your data downloads as a single file, something like time-kit-backup-2026-10-30.json. That file is yours; keep it wherever you like.
Restoring is one step: open the kit, choose the backup file, and everything is back. The same backup carries over to a new version. When you download an update, load your backup into it and your entries arrive unchanged.
Using it on a phone and on two devices
The file also opens in a phone browser. But there is no sync between phone and computer; each keeps its own data. We don’t hide that, because if you want “the same data everywhere”, a cloud app is the right tool.
For two devices, or two people (say you run the household budget with your partner), the practical way is:
- Keep the backups in a shared cloud folder.
- Before you start on a device, load the latest backup.
- When you finish, take a new backup and put it in the same folder.
If two people write at the same time, the last backup overwrites the one before, so you need to agree whose turn it is. And know this: if you put the backup in a cloud folder, that file lives in that cloud. The kit itself still sends nothing anywhere, but you have decided where things are kept.
Using it on a work laptop
Managers who want Manager Kit on a work laptop ask two things: will IT block it, and is it a problem to keep notes about the team?
Because the file sends nothing over the network, it opens without trouble in most places. Some companies do restrict downloaded files or the browser’s local storage. If you are unsure, ask your IT team about “an HTML file that opens in the browser and makes no network connections”; that sentence is usually enough.
About the notes: what you write about your people stays on your device. Keeping it in line with company rules and data protection law is your responsibility. Writing about behaviour rather than the person is both fairer and safer.
Why not the cloud?
The cloud’s benefits are real: access from every device, automatic backups, working together. We left them out on purpose, because each one means an account, a server and a subscription. In return, the file:
- asks for no account or password,
- works offline,
- is not affected if a service shuts down,
- does not sit anywhere someone else can look.
If you want to weigh which one suits you, Notion template, spreadsheet or HTML kit puts the three side by side.
How Productive Ant kits handle it
Time Kit, Money Kit and Manager Kit all work the same way: data stays in the browser’s storage, goes to a backup in one click and comes back in one step. The files load no outside code and connect to nothing. The whole approach is on the What is an HTML template? page.
Questions
Where does an HTML file save what I type?
In the storage of the browser you opened it with, on that computer. Nothing goes to the internet or a server. Open it in another browser or on another device and it starts empty; you move data with a backup file.
How often should I back up?
As often as you would hate to lose the work. A practical rule: once a week and after any big change. A backup is one JSON file and takes seconds.
Does keeping the backup in the cloud undo the privacy?
If you put the backup in a cloud folder, that file lives in that cloud. That is your choice. The kit itself still sends nothing anywhere; you decide where things are kept.