IBM watsonx.ai Lite (free tier)

The watsonx.ai Studio Lite free plan offers 10 Capacity Unit-Hours (CUH) per month (lowered by official documentation on 2026-09-14; previously 20 CUH), resetting automatically each month, valid long-term with no expiration; there's also a separate Runtime Lite free tier (roughly 300,000 tokens/month, not re-verified this round)

Re-checked 2026-09-18 (IBM official documentation at ibm.com/docs/en/watsonx, page marked Last Updated: 2026-09-14): the Studio Lite free plan's CUH allowance has been lowered from the previously recorded 20 CUH/month to 10 CUH/month; the restriction that 'each IBM Cloud account is limited to 1 watsonx.ai Studio instance, supporting only 1 user' is unchanged. The separate Lite plan on the watsonx.ai Runtime side (an estimated roughly 300,000 tokens/month) wasn't re-verified this round — the figure carries over from the previous record; the Runtime Lite page should be checked separately next round. Registration requires linking a credit card for identity verification, though the Lite plan itself isn't charged.

⚠️300K tokens/month is generally enough for everyday individual use (chat, small-scale RAG testing), and being a monthly-resetting standing free tier rather than a one-time credit, it's better suited to long-term use than the 'general-purpose credit' offered by comparable cloud vendors. The downside is the 1-instance, 1-user limit per account, unsuited to team collaboration.