Privacy Policy

Last updated: August 21, 2026

ZeroTabs is a new-tab dashboard. It pairs local browser storage with account sync through your KnowMan account. This policy explains what is stored where, what is synced, and the permissions ZeroTabs uses.

The short version

A free KnowMan account is required to use ZeroTabs. ZeroTabs syncs your tab sessions, notes, to-dos, focus history, and preferences (including display name and weather-location settings) to KnowMan's servers. This allows you to access your data across browsers and devices. ZeroTabs also allows you to create optional public share links for specific link lists. Bookmarks are read from your browser, managed only by you from the bookmarks panel, and stored locally only. ZeroTabs does load background photos from KnowMan's CDN (with an Unsplash fallback), sends anonymous usage analytics to PostHog (which you can turn off), and fetches website icons from DuckDuckGo and Google. ZeroTabs does not sell your data and has no ads.

Data stored locally

The following data is stored locally in your browser's storage (chrome.storage.local):

• Bookmarks (read from Chrome, displayed in the bookmarks panel)
• A local cache of your synced data (sessions, notes, to-dos, focus history, preferences)
• Your KnowMan authentication credential (API key)

Bookmarks are never sent to any server. The authentication credential is stored locally and sent only to KnowMan endpoints.

Account and synced data

A free KnowMan account is required to use ZeroTabs. You sign in via the KnowMan web app; authentication is handled by KnowMan (knowman.io).

The following data is stored on KnowMan's servers and tied to your account to enable sync across browsers and devices:

• Tab sessions
• Notes
• To-dos
• Focus history
• Preferences (including display name and weather-location settings)

This data is transmitted over HTTPS. You can remove this data from KnowMan's servers at any time by disconnecting or deleting your KnowMan account.

Public share links

You can create public share links for specific link lists you choose to share. These are unique URLs hosted on app.knowman.io.

Each share link contains only the link list you explicitly chose to share (titles + URLs). Anyone with the URL can view the list. A view counter is kept for the link. You can revoke a share link at any time from the extension. Nothing is shared without your explicit action.

Permissions

ZeroTabs requests the following Chrome permissions. Each is used only for the purpose described.

• storage — save a local cache of your synced data, bookmarks (read-only), settings, and your KnowMan authentication credential locally in the browser.
• bookmarks — read Chrome bookmarks to display them in the bookmarks panel, and let you manage them from that panel (create, rename, move between folders, delete) when you choose to. Bookmarks are never sent externally.
• tabs — read open tabs ONLY when the user runs a "sweep" to save them as a session. No background browsing monitoring.
• tabGroups — read and recreate Chrome tab groups so a saved session preserves and restores its tab-group structure.
• contextMenus — add a right-click "ZeroTabs" menu (sweep tabs, open dashboard, recent sessions).
• alarms — schedule the end of a focus/pomodoro timer so its completion reminder fires reliably, even when the dashboard tab is not focused. No other background activity.
• notifications — show a desktop notification when a focus or break timer completes. Used only for the focus timer you start; no marketing or other notifications.

ZeroTabs does not declare Chrome's geolocation permission. Precise location, when you opt in, uses the browser's standard geolocation API and is gated by Chrome's own permission prompt — the same prompt any website shows. It remains off by default. See the Location section below.

External services

ZeroTabs communicates with a small number of external services:

• Background photos (media.knowman.io) — the curated CC0 wallpaper library is served from KnowMan's own CDN. If one of those images fails to load, ZeroTabs falls back to a small pool of hotlinked Unsplash photos (images.unsplash.com), shown with attribution. In both cases only the image request is made; no account, key, or identifier is attached.
• PostHog (us.i.posthog.com, us-assets.i.posthog.com) — anonymous usage analytics. This can be disabled in Settings. No browsing history or keystrokes are recorded.
• KnowMan API (api.knowman.io, app.knowman.io) — a KnowMan account is required. ZeroTabs syncs your tab sessions, notes, to-dos, focus history, preferences, and reading queue with KnowMan. Your authentication credential is stored locally and sent only to KnowMan endpoints.
• Weather: wttr.in (wttr.in) — used for automatic, IP-based location only. See the Location section below.
• Weather: Open-Meteo (api.open-meteo.com) — the forecast provider used whenever a location is known as coordinates or as a named city, and as a fallback for automatic mode. See the Location section below.
• Open-Meteo geocoding (geocoding-api.open-meteo.com) — converts a city name into coordinates so a forecast can be fetched for it. Only the city name is sent; no account, key, or identifier is attached.
• BigDataCloud reverse geocoding (api.bigdatacloud.net) — used only when you enable precise location, to turn your coordinates into a city name so the app can show where you are instead of a timezone's name. ZeroTabs does not contact BigDataCloud directly: the request goes through KnowMan's server, so BigDataCloud never receives your IP address or any browser identifier. Only rounded coordinates are forwarded. See the Location section below.

Favicons

Favicons (website icons) for bookmarks, tabs, and reading-queue items are fetched from DuckDuckGo (icons.duckduckgo.com) and Google (google.com/s2/favicons). Only the domain name is sent to these services, never the full URL or any page content.

Location

By default, the weather widget determines your approximate location from your IP address via wttr.in. No browser permission prompt is shown for this, and no coordinates are involved.

You can optionally switch to a more precise location in Settings, with two choices:

• Precise location (opt-in) — uses the browser's geolocation API to get your device's exact coordinates. This triggers a Chrome permission prompt the first time, and is off by default. You must explicitly turn it on.
• Manual city — type in a city name instead; no coordinates or permissions involved.

If you enable precise location, your coordinates are sent directly from your browser to Open-Meteo (as query parameters) to fetch the forecast.

Turning those coordinates into a city name works differently. The coordinates are first rounded to roughly 110 metres, then sent to KnowMan's server, which forwards only that rounded pair to BigDataCloud and returns the city name. Your exact coordinates, your IP address, and your browser's identity are never exposed to BigDataCloud. The rounded pair is cached on the server for a period so that repeated lookups for the same rough area do not need to be repeated; that cache holds only the rounded coordinates and the resulting place name, and is not associated with you or your account.

Your unrounded coordinates are not stored anywhere beyond your local settings (used to avoid re-prompting on every new tab).

If you choose a manual city, the city name is sent to Open-Meteo's geocoding service to resolve it to coordinates, which are then used for the forecast. The resolved coordinates are cached locally so the same city is not looked up repeatedly.

You can turn precise location off at any time in Settings, which reverts to IP-based auto-detection or manual city. The weather widget itself can also be disabled entirely in Settings.

Weather for cities you add

The cities you add to the world-clock and weather list are also weather targets. To show each one's temperature and forecast, ZeroTabs sends that city's name to Open-Meteo's geocoding service and then requests its forecast — the same two services described above, and nothing more.

• Only the city names you yourself added are sent. No identifier, account, or device information is attached to these requests.
• Forecasts are cached on your device for 30 minutes, and each city's coordinates are cached indefinitely, so opening a new tab usually makes no network request at all.
• Weather is fetched for at most 10 cities. Any beyond that show the time only.
• Weather data itself is never synced or sent to ZeroTabs or KnowMan servers — it is fetched by your browser and stored only on your device.

What ZeroTabs does NOT do

• ZeroTabs does not sell your data.
• ZeroTabs shows no ads.
• ZeroTabs does not track your browsing history.
• ZeroTabs does not use cookies for tracking.
• ZeroTabs does not send your bookmarks to any server.
• ZeroTabs only syncs the data listed in the "Account and synced data" section, and only to KnowMan.

Contact

Questions about this policy? Contact us at [email protected].

ZeroTabs is built by KnowMan.