Text-to-Speech: Lightning v3.1 Pro checkpoint `lightning_v3.1_pro_10_26` in preview
A new Lightning v3.1 Pro checkpoint for English (en), Spanish with English code-switching (es) and Hindi with English code-switching (hi) is in preview until 2026-11-28. Try it by passing "model": "lightning_v3.1_pro_10_26" on any TTS endpoint. Every Pro voice works on it.
Only English, Spanish and Hindi change on 2026-11-28. On that date, the preview becomes the stable lightning_v3.1_pro for those three languages, including requests that omit language, so use "model": "lightning_v3.1_pro" from then on. lightning_v3.1_pro_10_26 remains available for 30 more days, until 2026-12-28. The other 28 languages and auto stay on their current checkpoints. The scheduled change is listed on Deprecation Notices.
Details, recommended voices and benchmarks are on the Lightning v3.1 Pro model card and in the Lightning v3.1 changelog.