Are the APIs really OpenAI- and Anthropic-compatible?
Yes. Use the official SDKs or any compatible client — just swap the base URL and key. Responses, Chat Completions, and Messages all work as expected.
What are completion windows?
Completion windows let you indicate your latency tolerance and drastically cut token costs. balanced and flex give Sail more scheduling room in exchange for lower token prices. A completion window can be optionally specified on each request to Sail's API, and the pricing page shows which windows each model supports.
No strict rate limits and no limit-increase process. Sail is designed to absorb large bursts of traffic, and the flex completion window is best for maximum throughput on very large workloads.
Is Sail SOC 2 compliant?
Sail is SOC 2 Type I compliant, and SOC 2 Type II compliance takes effect August 25, 2026. You can review our security controls and request the Type I auditor report in our Trust Center.
We have Zero Data Retention (ZDR) by default, and use inference request and response data only to provide the service and never train models on it without your written consent. Our DPA covers the default terms, and enterprise customers can sign a DPA.
Writing CUDA to push toward speed-of-light performance on GPUs
Digging into the guts of inference engines like SGLang to maximize efficiency
Distributing work across providers to maximize robustness and fleet utilization
Using spot compute when it's available, and safely failing over to more reliable compute when it's not
Which models are supported?
The leading open models, listed here, with support for LoRA fine-tunes.
Do you support fine-tunes? RL rollouts?
Yes. Bring your own LoRA adapters and run them on supported models. If you train LoRAs with Tinker, you can also sample directly from Tinker checkpoints without uploading, and use Sail as a drop-in TokenCompleter in Tinker.
How is pricing structured?
Usage-based, pay-per-token, and extremely competitive, with $5 in free credits refreshed every month. Enterprise contracting is also available (contact us).