The Tokyo-headquartered firm said it would sell 13 million new shares in Japan and 22 million shares overseas for an indicative price of JPY 2,800 each.
That would value the entire company at 588 billion JPY ($5.5 billion).
Line is currently 100 percent owned by South Korea's largest web portal operator, Naver Corp, which may offer as many as 5.25 million existing shares in the event of excessive demand.
Altogether, as many as 40.25 million shares will be sold, valuing the IPO at as much as JPY 112.7 billion.
Line said it plans to use the proceeds for strategic investments including global mergers and acquisitions, and to repay debt.
Line launched its messaging app in 2011 under the name NHN Japan as a communication tool prompted by the chaotic aftermath of a devastating earthquake and tsunami in March that year. It rebranded to Line in 2013.
Its IPO would be the largest in Japan since the $12 billion partial privatisation of Japan Post and its bank and insurance divisions in November.
Line has hired Morgan Stanley, Goldman Sachs, JPMorgan and Nomura to manage the IPO.
© Thomson Reuters 2016
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