"Free" means a plan that stays free, credit that runs out, or software you run yourself (vendor pages, 2 October 2026):
| Offer | What you get | Card at sign-up | When it ends | Here |
|---|---|---|---|---|
| Aiven Free plan | One small Kafka service, no time limit | No | Never; powers off when idle | Run (Aiven's Free Kafka Plan) |
| Redpanda 64,862 Serverless | $100 credit for 30 days | No | Suspended, deleted 7 days later | Not run |
| Confluent Cloud 17,245 | $400 credit for 30 days | No | Suspended until a payment method | Not run (Pricing and Free Trial) |
| StreamNative Cloud | $200 credit | No | Not stated on its pages | Not run |
| WarpStream | $400 credit, no expiry | No | Agents run on your cloud bill | Not run (WarpStream) |
| Instaclustr | 30 days, one small cluster | No (developer nodes) | Billing details to continue | Not run |
| MSK, Event Hubs, Google | No free tier | Yes (cloud account) | Pay as you go | Not run (MSK, Event Hubs, Google Kafka) |
| Upstash 120,363 Kafka | Discontinued 11 March 2025 | - | - | - |
| Kafka or Redpanda in Docker 514 | Everything, on your machine | No | Never | Run (6.3, Redpanda) |
Only one managed service is free indefinitely with no card: Aiven's Free plan, and it earns the "free" with its limits (250 KiB/s, five topics, three-day retention). Every credit-based trial needs a payment method once the credit or the month is gone, and some delete your data soon after. Learn the broker on the local cluster of Kafka 4.x in Docker, which lets you stop brokers and read segment files, and use a free managed plan to learn what a provider adds and takes away. Offers change often: check before relying on a row.