Privacy

SEKAI has no accounts and no advertising. Almost everything you do stays in your browser. This page lists exactly what does not.

Last reviewed 2026-10-29.

Stays in your browser

• Your workspace (projects, conversations, presets, agents, run history and settings) is saved in this browser’s own storage (local storage and IndexedDB), together with the images and audio you generate.
• Your Journey (progress, discoveries, rewards and preferences), saved viewpoints, field-guide notes, the photo album and world settings are stored the same way, on this device only.
• API keys stay in memory for the current tab. Whether you paste an OpenRouter or provider key or sign in with OpenRouter, the key is never written to storage, and it is removed from backups, cloud sync and share links. Closing the tab forgets it.
• Share links carry their content after the # in the address. Browsers do not send that part to any server.
• Clearing this site’s data in your browser deletes all of it. Export a backup first from Your workspace › Connections & storage if you want to keep it.

Model requests go straight to the provider

• When you chat, create, compare or run agents, your browser sends the prompt and any attachments directly to OpenRouter, or to the provider or local server you connected, using your key. SEKAI’s servers are not in that path and never see the content.
• Those requests are covered by the privacy terms of OpenRouter and of the model provider that serves them. Signing in with OpenRouter also happens between your browser and openrouter.ai.

What reaches SEKAI’s servers

• Model catalog. The workspace can ask /api/catalog for the current OpenRouter model list, to show models added since the bundled snapshot. The request carries no personal data, and the answer is cached and shared by everyone.
• Cloud sync, only if you turn it on. Your browser encrypts the workspace and Journey with AES-256-GCM. The key comes from your sync code through PBKDF2-SHA-256 (310,000 rounds) and never leaves the browser. The server stores only the ciphertext, its salt and nonce, and a timestamp, under a SHA-256 hash of the sync code, for up to 400 days after the last upload. Keys and other secrets are stripped before encryption. Without the sync code, nobody, including us, can read the copy.
• Error reports. On the hosted site, an uncaught error, a failed promise or a lost WebGL context sends one short report to /api/report, at most five per page view and never from a local or offline copy. A report contains the kind of error, its message (up to 500 characters), stack trace (up to 4,000), the script file and line, the page path with up to 40 characters of the address after #, and the release. The server adds your browser’s user-agent string, the country from Vercel’s network, and your IP address with its last part removed. Reports are written to the Vercel function logs and are not stored anywhere else.
• Visitor statistics. The homepage and world load Vercel Web Analytics and Speed Insights. They count page views, referrers, country, browser and device type, and loading performance, in aggregate. They do not use cookies or follow you across sites. The guide pages, including this one, load neither.

Opt-in features that share something

• Lanterns (visitor presence). Off until you turn them on. While on, your browser sends /api/presence a random identifier that is new for each tab, the province you are in and a coarse map cell. Other visitors see a lantern in that cell, never the identifier. Entries expire after one minute, and turning the toggle off or leaving the province removes yours immediately.
• Shared arena leaderboard. Off until you choose to share votes. Each shared blind-arena vote sends /api/arena only the two model IDs and the outcome. These are added to anonymous pair counts. Your prompts and the answers never leave your browser.
• Lantern notes. Only when you hang one: the text of the note, the province and the spot are sent to /api/social and shown to other visitors for seven days. No name or identifier is attached. A note reported by three visitors is removed.
• Photo wall. Private by default. Only a photo you choose to publish is sent, as a small copy (at most 640 pixels and 64 KB) with location and camera data removed in your browser and again on the server. It is public for 14 days, or until you remove it or three visitors report it.
• Walking together. Only after you start or join a walk. Invite messages pass through /api/social for a few minutes; then browsers connect directly with WebRTC and exchange only positions, emotes and the name you chose. A direct connection shows the other walkers your IP address, and a public STUN server (Google) sees it while finding a route.
• Weekly challenge. Reading the shared count sends nothing about you. If you opt in, your browser adds a number (villages, provinces or quests this week) to an anonymous counter.
• Visiting a study. A study link carries the furnishings, stamps, rewards and outfit inside the link itself; opening it sends nothing to a server.
• Local weather. Off until you turn it on in World settings. Your browser then sends Open-Meteo (open-meteo.com, no account or key) either a town name you type or your approximate position rounded to 0.1° (about 11 km), and receives the current weather. It is asked at most every 30 minutes and the answer is kept in this browser. SEKAI’s servers are not in that path.
• Rate limits. Sync, presence and arena requests use your IP address as a short-lived counter key against abuse: one minute for each request window, and a day for the arena’s daily vote limit. The counter keys are then deleted. The Together features, report de-duplication and the arena’s one-vote-per-pair-per-day rule use a salted hash of the address instead, kept for at most a week (two for photo reports).

Hosting

• The site is served by Vercel. Like any web host, Vercel processes your IP address and request headers to deliver pages and protect the service. Synced data and the presence and arena counters are kept in an Upstash Redis database.
• There is no advertising and no tracking pixels. Nothing is sold or shared with third parties beyond the services named on this page.

Questions or corrections are welcome. The code that does all of this is part of the SEKAI repository.