LTX-2.3¶

Development line: project:ltx-video · thread ltx-video
Last event: 2026-07-30 · 3 dated since 2026-03-05 · Researched: 2026-09-04 · confidence: medium

What it is¶

LTX-2.3 is a 22B DiT-based audio-video foundation model for teams generating synchronized video and audio locally, in ComfyUI, or through the LTX API.

• Generation: text-to-video and image-to-video.
• Pro features: audio-to-video, Retake, Extend, and Reframe.
• Weight paths: dev, distilled, fp8, and latent-upscaler checkpoints.

22B parameters; the current Hugging Face repository is 156 GB and the dev checkpoint alone is 46.1 GB. We keep it for existing integrations and 2.3-specific adapters; begin new multi-shot, footage-editing, or deep fine-tuning work on LTX-2.5.

Development line¶

• 2026-03-05 — LTX-2.3 was presented with documentation and a text-to-video playground. Fast handled text/image-to-video, while Pro added audio-to-video, Retake, and Extend; 22B dev/distilled weights and latent upscalers shipped.
• 2026-03-05 — LTX-2.3 model files and a ComfyUI text-to-video workflow were linked. Fast handled text/image-to-video, while Pro added audio-to-video, Retake, and Extend; 22B dev/distilled weights and latent upscalers shipped.
• 2026-07-30 — An LTX-2.3 22B IC LoRA for relighting was published. On 2026-07-30, a Hugging Face resource named LTX-2.3-22B-IC-LoRA-Relight was linked. This is a material extension of the LTX-2.3 line because it adds a specialized relighting capability through a LoRA resource.

What changed¶

• 2026-03-05 — LTX-2.3 became the API default: Fast handled text/image-to-video, while Pro added audio-to-video, Retake, and Extend; 22B dev/distilled weights and latent upscalers shipped.
• 2026-04-23 — Asynchronous HDR conversion added SDR-to-EXR output.
• 2026-05-03 — Async V2 expanded to text-to-video, image-to-video, audio-to-video, Retake, and Extend.
• 2026-07-02 — LTX-2 was deprecated, with temporary automatic routing to LTX-2.3.
• 2026-07-07 — Asynchronous video reframe added generated fill for a new aspect ratio.
• 2026-07-30 — LTX-2.3-22B-IC-LoRA-Relight added controlled exterior-video relighting from a source clip plus a light-direction ball.
• 2026-08-02 — LTX-2.3 text-to-video and image-to-video gained a 720p tier.
• 2026-08-11 — LTX-2.5 added Fast up to 4K, Pro at 720p/1080p, camera motion, last-frame image-to-video, and automatic duration; it is now the recommended starting point.
• 2026-08-16 — LTX-2 API model IDs stopped working; remaining migration targets are LTX-2.3 and LTX-2.5.

How to use this¶

From 2026-03-05, practitioners can use LTX-2.3 through its documented text-to-video route or the linked ComfyUI workflow; from 2026-07-30, they should evaluate the dedicated 22B IC relighting LoRA when relighting is required.

1. Keep LTX-2.3 for a working integration or a 2.3-specific adapter; select LTX-2.5 for a new project. — https://ltx.io/model/ltx-2-3
2. Create a Developer Console API key, then submit a text-to-video or image-to-video request. — https://docs.ltx.video/quickstart
3. Use ltx-2-3-fast for text/image previews; use ltx-2-3-pro when the workflow needs audio-to-video, Retake, Extend, or Reframe. — https://docs.ltx.io/models/ltx-2-3
4. For production, submit a V2 async job, retain its job ID, poll to completion, and download the result URL. — https://docs.ltx.io/async-jobs
5. For a local run, clone LTX-2, run uv sync, download LTX-2.3 plus Gemma 3 12B, then choose the distilled pipeline for speed or the two-stage HQ pipeline for quality. — https://huggingface.co/Lightricks/LTX-2.3/blob/main/README.md
6. In ComfyUI, update ComfyUI first, load the supplied text-to-video workflow, and place its fp8 checkpoint, LoRAs, and spatial upscaler in the named model folders. — https://github.com/Comfy-Org/workflow_templates/blob/main/templates/video_ltx2_3_t2v.json
7. For exterior-video relighting, use the official single-stage graph with the Relight IC-LoRA at weight 1.0 and a source clip carrying the light-direction ball. — https://huggingface.co/Lightricks/LTX-2.3-22b-IC-LoRA-Relight

Best practices¶

• Treat width and height divisible by 32 and frame count divisible by 8+1 as an input contract; otherwise pad with -1 and crop after generation. — https://huggingface.co/Lightricks/LTX-2.3/blob/main/README.md
• Write one focused, chronological shot with explicit action, camera, lighting, and audio; rewrite prompts from other video models instead of pasting their tags or shot lists unchanged. — https://docs.ltx.io/api-documentation/implementation-guides/prompting-guide
• Use Fast for iterative text/image generation and reserve Pro for the endpoint set that requires it. — https://docs.ltx.io/models/ltx-2-3
• Use asynchronous jobs for production workloads rather than holding a long-lived synchronous connection. — https://docs.ltx.io/async-jobs
• For Relight, stay with exterior footage, align the ball-bearing reference to the target clip, use the minimal direction prompt, and avoid the true two-stage path because Stage 2 drops the conditioning. — https://huggingface.co/Lightricks/LTX-2.3-22b-IC-LoRA-Relight
• When migrating from LTX-2, retrain custom LoRAs for LTX-2.3’s latent space instead of assuming drop-in compatibility. — https://ltx.io/model/ltx-2-3

Superseded by this¶

• 2026-03-05 — “Custom LTX-2 LoRAs work unchanged on LTX-2.3” is obsolete; retraining is required for the 2.3 latent space.
• 2026-08-11 — “LTX-2.3 is the recommended start for a new project” is superseded by LTX-2.5; LTX-2.3 remains supported for existing integrations.
• 2026-08-16 — “ltx-2-fast and ltx-2-pro remain valid API model IDs” is obsolete; those requests return errors.

Still unknown¶

• The 2026-07-30 item is a first-party IC-LoRA adapter release, not a new LTX-2.3 base checkpoint; available sources do not define whether every adapter release belongs in the core-model history.
• The Relight model card does not display an independent publication date, so its timing is anchored to 2026-07-30 while its technical scope is first-party verified.
• The original Studio text-to-video URL now redirects to the Studio home; without a dated snapshot, its exact 2026-03-05 interface and availability cannot be reconstructed.

Sources¶

Agent brief¶

• Subject: project:ltx-video, thread ltx-video, 3 dated events 2026-03-05 → 2026-07-30.
• Practical note: From 2026-03-05, practitioners can use LTX-2.3 through its documented text-to-video route or the linked ComfyUI workflow; from 2026-07-30, they should evaluate the dedicated 22B IC relighting LoRA when relighting is required.
• Confidence: medium. Dated supersedes above are the authority for what is obsolete.