"I try to focus on a long-term view of building a really durable business," he said in an interview with CNBC from the Re/code Code Conference on Wednesday. "That includes making sure we're investing into growth as balanced against operating efficiency and operating leverage in service to increasing margins over time.
"I think if we do that, in the long term the value of the company will be reflected in the financial results we deliver."
Costolo also brushed off any comparisons to Facebook and Internet analyst Mary Meeker's comments at the technology news website's conference that Facebook's average revenue per user is twice that of Twitter.
Twitter's revenue per user is "growing quite well," he said.
"It's specifically up because engagement on the platform, engagement per tweet is up so much over the course of the last year," he said.
He also said the company is pursuing "in-the-moment" commerce, to enable spontaneous purchases by users.
"Instead of searching for something to buy, we want to make it easy for you to see something mentioned, and then easily buy it," he said.
—By CNBC's Michelle Fox, additional reporting by Julia Boorstin.
Disclosure: NBC News group is a minority stakeholder in Re/code and has a content sharing partnership with it.