Getting Started with KnowCO₂

Welcome! Choose the path that fits how you want to use your KnowCO₂ monitor – from completely offline use to full cloud integration. Each option builds on the previous one, so feel free to stop whenever you’re satisfied.

Option 1: Turn it on & go (Offline mode)

This is the simplest way to use KnowCO₂: no Wi‑Fi required. Just power it up and read the air quality on the screen.

  1. Power up. Connect the device to a USB‑C power source. It powers on automatically. The SCD41 sensor warms up in about 60 seconds.
  2. Ignore the network. On first boot the monitor starts in Access Point (AP) mode and shows its own Wi‑Fi network name and password plus a QR code. If you only want to monitor locally, simply ignore these credentials—the device works fully offline in this state.
  3. Read your air. The display shows CO₂ (ppm), temperature and humidity. Use the bottom button (A) to toggle between °C/°F. Use the middle button (B) to cycle through the three views: detailed (ppm, temperature, relative humidity), a large CO₂ number, and a rolling graph.
  4. Optional: hide AP info. A short press of the top button (C) toggles between the main display and the AP info screen. The AP info screen shows the network details and QR codes; press C again to return to the main display for continuous readings.
No data ever leaves the device when you remain offline. You can always connect it to Wi‑Fi or the cloud later without losing functionality.

Option 2: Connect to Wi‑Fi (Local network)

Connect your KnowCO₂ to your home or office Wi‑Fi to configure settings via a web page and synchronize time. In this mode all data stays on the device – nothing is sent to the cloud unless you explicitly enable it.

  1. Enter AP mode. On the very first boot the device is already in Access Point (AP) mode. If you’ve been using it in STA mode, hold the top button (C) for about 2 seconds to switch back to AP mode. You’ll see AP on the screen and the SSID/password will update.
  2. Join the device network. On your phone or computer, connect to the Wi‑Fi network displayed on the screen (e.g. KnowCO2‑XXXX). Use the password shown or scan the QR code.
  3. Open the settings page. Once connected, open http://192.168.4.1 in your browser. You’ll land on the local settings page served from the device itself.
  4. Optional: customize the AP. In the “Access Point (AP) Wi‑Fi” section of the page you can change the device’s network name and password to something memorable, and set an admin password to protect the settings page. Click Save to store these changes.
  5. Select your Wi‑Fi network. In the “Station (STA) Wi‑Fi” section choose your home or office network from the dropdown, enter its password and click Save. The device stores these credentials securely.
  6. Switch to STA mode. After saving your home network, hold the top button (C) for about 2 seconds. The monitor reboots, switches to Station (STA) mode and attempts to connect to your network. You’ll see STA on the screen. If connection fails, hold C again to return to AP mode.
  7. Reconnect to your normal Wi‑Fi. Rejoin your usual Wi‑Fi network on your phone or computer. The KnowCO₂ screen now shows either an IP address or a .local hostname (e.g. knowco2‑XXXX.local) where the device can be reached on your network.
  8. Wait for time sync. The monitor automatically synchronizes its clock via NTP. When this is complete, the tiny Wi‑Fi indicator in the top‑right corner of the display changes from WIFI to TWIFI, indicating that time has been synchronized.
  9. Adjust settings & explore endpoints. Visit the device at its new address (e.g. http://knowco2‑XXXX.local). From here you can tweak thresholds, graph scaling, display modes, regenerate AP credentials and more. The page also lists JSON endpoints such as /status (current readings, battery and metadata) and /data (CO₂ history) which are useful for integrations.
Connecting to Wi‑Fi automatically keeps the internal clock synced and lets you adjust settings from any browser on your network. You can remain in this local‑only mode indefinitely—nothing is uploaded unless you enable the cloud.

Option 3: Cloud & Apps (Full experience)

Enable cloud connectivity to log readings over time, receive alerts and access your data from anywhere. You’ll need a KnowCO₂ cloud account and the device’s unique ID.

  1. Complete Wi‑Fi setup. Ensure your monitor is in Station (STA) mode and reachable on your network (see Option 2). For best results, wait until the top‑right indicator shows TWIFI — this means the device’s clock is synchronized.
  2. Create a cloud account. Visit cloud.knowco2.com (or use the iOS/macOS app) and sign up. Add a new device using the ID displayed on your KnowCO₂ screen (on the AP info screen) or shown in the “Device ID” field on the settings page.
  3. Obtain a device token. The cloud portal or app will generate a secret token for your device. Keep this token secure and never share it publicly.
  4. Enter credentials on the device. Open the local settings page (http://knowco2‑XXXX.local) and scroll to the “Cloud” section. Paste in the device ID and token, choose your upload interval (e.g. 60 s), and enable cloud upload. Click Save.
  5. Verify upload. When data is sent successfully, the tiny indicator at the top of the screen briefly shows “CLOUD”. You can now view live and historical readings, set alert thresholds and share access from the web dashboard or mobile apps.
Cloud upload uses secure HMAC authentication. Your monitor continues to operate if Wi‑Fi drops; queued data will be sent once connectivity is restored.