You can edit any message up to 15 minutes after sending, and it’ll update for everyone in the chat. Edited messages will have the word “edited” next to the timestamp.
If you aren’t on the latest version of WhatsApp you’ll see, “This message was edited for everyone in this chat on the latest version of WhatsApp.” Update your app to see edited messages.
How to Edit a Message:
Long press the message you want to edit, then tap More options
Select Edit and update your message.
When you’re finished, tap the check mark to update your message.
Note:
There is a 15 minute time limit for editing messages.
Editing a message won’t send a new chat notification to people in your chat.
You can’t edit photos, videos, or other types of media.