As of my last update in January 2022, the top Bitcoin exchanges in the world were:
1. **Binance**: Binance is one of the largest cryptocurrency exchanges by trading volume. It offers a wide range of cryptocurrencies for trading, including Bitcoin (BTC), and provides various trading pairs and trading products.
2. **Coinbase**: Coinbase is a popular cryptocurrency exchange based in the United States. It is known for its user-friendly interface and is often the first choice for many beginners entering the cryptocurrency space.
3. **Kraken**: Kraken is another well-established cryptocurrency exchange known for its security features and robust trading platform. It offers a variety of cryptocurrencies for trading, including Bitcoin, and serves users worldwide.
4. **Bitfinex**: Bitfinex is a cryptocurrency exchange offering advanced trading features such as margin trading and liquidity swaps. It has a significant trading volume and is popular among experienced traders.
5. **Huobi**: Huobi is a cryptocurrency exchange based in Singapore with a global presence. It offers a wide range of cryptocurrencies for trading, including Bitcoin, and provides various trading tools and services.
Please note that the cryptocurrency exchange landscape is constantly evolving, and the rankings may have changed since my last update. It's essential to conduct thorough research and consider factors such as security, fees, liquidity, and supported features before choosing a cryptocurrency exchange.