How can you know if someone is online on WhatsApp without opening the chat?

To determine if someone is online on WhatsApp without opening the chat with them, you can observe a few indicators within the app. Here are the main ways to infer if someone is online:

1. **Online Status in Chat List**:
   - In the WhatsApp chat list, you might see a contact's status as "Online" below their name. This indicates that the person is currently active on WhatsApp.

2. **Profile Picture Changes**:
   - If you notice sudden changes in someone's profile picture, it could suggest they are active on WhatsApp, as they may have recently updated their profile.

3. **Status Updates**:
   - Check the status updates of the person. If they have posted a recent status, it implies they have been active on WhatsApp recently.

4. **Typing Indicator**:
   - If you have a chat open with the person or in a group chat, a typing indicator (three dots) next to their name indicates they are actively composing a message.

5. **Last Seen Timestamp**:
   - The "Last Seen" timestamp, if visible, shows when the person was last active on WhatsApp. Although not real-time, it gives you an idea of their recent activity.

### Important Notes:
- **Privacy Settings**: Users can customize their privacy settings in WhatsApp, such as disabling "Last Seen" timestamps and online status visibility. If these settings are disabled, you won't be able to see when they were last active or their current online status.
 
- **Respect Privacy**: It's essential to respect others' privacy and avoid using third-party apps or methods that violate WhatsApp's terms of service or compromise privacy. WhatsApp values user privacy and restricts direct real-time monitoring of users' online status for this reason.

By observing these indicators within the WhatsApp app, you can get a general idea of whether someone is currently active or online without needing to open a chat with them directly.