The next halving will happen at block: 1,050,000
This means that 201,339 blocks are left and it will approximately happen in..
1,475 days or
35,400 hours or
2,123,986 minutes!

What is it all about?

Halving is an anti-inflation mechanism implemented, in the Bitcoin network. As the name suggests a reduction in the supply of new coins is cut by half (50%). This causes BTC inflation to fall cyclically. It takes place whenever 210,000 blocks have been mined which is roughly around once every 4 years. Current mining rewards are 3.125 bitcoins.
Bitcoin: A Peer-to-Peer Electronic Cash System