Twitter said on Tuesday that it would begin a test with a random sample of users allowing them to send tweets that are as long as 280 characters, double the existing cap.
Twitter curently is limiting messages to 140 characters.
The company said its emphasis on brevity would never change but that it had been wondering whether people could express themselves easily enough, hurting the service's popularity.
"Trying to cram your thoughts into a Tweet - we've all been there, and it's a pain," Twitter project manager Aliza Rosen and senior software engineer Ikuhiro Ihara said in the post.
A higher character limit was inspired by how people use Twitter when writing in Chinese, Japanese and Korean, the company said. Characters in those languages can often express more than Roman characters can, meaning those users already, in effect, have a higher limit.
The test of 280 characters will run for an unspecified number of weeks in all languages except Chinese, Japanese and Korean, Twitter said.
Though Twitter is ubiquitous in media but still, the company has struggled financially.