Indian Central Water (ICW) and Subantarctic Mode Water (SAMW) formation rates are estimated from two air-sea flux products, the Comprehensive Ocean-Atmosphere Data Set (COADS) and the Southampton Oceanography Centre (SOC) climatology. The ICW formation is estimated to be 8 Sv (1 Sv = 10~(6)m~(3)·s~(-1) ) from both products, with more contributions from freshwater flux. From the COADS product, the SAMW formation rate is estimated to be 31 Sv in the potential density range of 26.5-26.9σ_θ, with also a significant contribution from freshwater flux. However, the SAMW formation rate estimated from the SOC product is much smaller, which may be due to bias of the SOC heat flux. Poorer quality of the flux products in the Southern Ocean may also contribute to the difference. Indian Central Water (ICW) and Subantarctic Mode Water (SAMW) formation rates are estimated from two air-sea flux products, the Comprehensive Ocean-Atmosphere Data Set (COADS) and the Southampton Oceanography Center (SOC) climatology. The ICW formation is estimated From the products with the more contributions from freshwater flux. From the COADS product, the SAMW formation rate is estimated to be (1 Sv = 10 ~ (6) m ~ (3) · s -1) However, the SAMW formation rate estimated from the SOC product is much smaller, which may be due to the bias of the SOC heat flux. Poorer quality of the flux products in the Southern Ocean may also contribute to the difference.