Intercom, which provides various customer-facing products for online businesses, announced today that it has raised a whopping $125 million led by Kleiner Perkins Caufield and Byers. New investor GV joined existing investors Bessemer Venture Partners, Index Ventures, and others in the round. This cash injection brings Intercom’s post-money valuation to $1.275 billion.

The San Francisco-based startup says it now has more than 25,000 customers, including Airtable, New Relic, Product Hunt, Shopify, and Sotheby’s. The startup charges a monthly subscription fee that varies depending on which products a customer uses and how many people are using it. Subscriptions range between $29 and $49 per month.

Products include Messages, Inbox, and Articles to help companies onboard new customers, chat with their users, and convert sales leads. Intercom launched Live Chat for Sales last September.

The startup says it powers 500 million conversations a month, or 6 billion conversations annually.

Competitors in this space include Zendesk, Freshdesk, and Marketo.

To date, Intercom has raised a total of $241 million. It will use the fresh injection of capital to further develop its platform, add more features, and double its product and engineering teams over the next 18 months.

“Recently, we’ve seen the most growth around our tools for sales and marketing teams,” wrote Intercom cofounder and CEO Eoghan McCabe, in an email to VentureBeat. “When our customers use Intercom’s Messenger to engage website visitors, conversion rates and sales increase by 82 percent. There’s enormous opportunity for internet businesses to use Intercom in that way, and we’ll be focused on building products that help businesses accelerate growth.”

Kleiner Perkins partner Mary Meeker will be joining the Intercom board.

Founded in 2011, Intercom now has just under 500 employees across its offices in San Francisco, Dublin, Chicago, London, and Sydney.

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