The largest mollusk is the colossal squid (Mesonychoteuthis hamiltoni). It has 12 – 14 m (39–46 ft) in length and about 400 kg (881,84 lb) in weight.
Source: https://dinoanimals.com
The largest recorded specimen was captured in 2007. It was initially estimated to measure 10 m (33 ft) in length and weigh 450 kg (990 lb) but study on the specimen later showed its actual weight was 495 kg (1,091 lb), but it only measured 4.2 m (14 ft) in length.
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