3.The story
- 2015 First TPU starts running inside Google's data centres, for running models only 2.
- 2016 Google reveals the TPU publicly; it had helped power AlphaGo 17.
- 2017 TPU v2 can also train models; Google starts renting TPUs 18.
- 2018 TPU v3 needs liquid cooling, a first for Google's data centres 19.
- 2021 TPU v4: one pod passes an exaflop 20.
- 2023 TPU v5e and v5p 21 22.
- 2024 Trillium (TPU v6e) 23.
- 2025 Ironwood (TPU7x), built for running AI models 24.
- 2026 Eighth generation split into two chips, TPU 8t and TPU 8i 5.
Google built the first TPU for its own needs. When it revealed the chip in May 2016, it said TPUs had been running in its data centres "for more than a year", powering RankBrain search, Street View and AlphaGo 17. The first TPU only ran trained models; TPU v2 in 2017 could train them too, and Google offered 1,000 of them free to researchers 18. From TPU v4, Google linked thousands of chips with optical switches that can rewire the network 25.
Google's own paper on the first TPU reported 15 to 30 times the speed of contemporary GPUs and CPUs on its workloads, and 30 to 80 times the performance per watt 2. Its 2023 paper on TPU v4 described a 4,096-chip machine in service since 2020, 1.2 to 1.7 times faster than NVIDIA's A100 while using 1.3 to 1.9 times less power, on Google's comparison 25. Ironwood was announced in April 2025 24; Google's release notes list it in preview from 24 November 2025 and generally available from 31 March 2026 26.