Threads, the social media app aimed at rivalling Twitter, has signed up more than 100 million users in less than five days, according to new data.
It means Threads, launched by Instagram-owner Meta, has beaten a record set by Open AI's ChatGPT app.
Threads went live on Apple and Android app stores in 100 countries last Wednesday.
But it is not available in Europe yet because of uncertainty over EU data privacy legislation.