LightOnOCR-3-0.8B
Smallest model. LightOnOCR-3-0.8B is the lightest model of LightOn's LightOnOCR-3 family, with the same layout and visual understanding features.
About LightOnOCR-3
LightOnOCR-3 is a new family of highly performant lightweight OCR models. Compared to the previous generation, they bring significant improvements in speed and transcription quality and introduce new visual understanding features: the models now output bounding box coordinates with labels for all visual elements of a document, short descriptions of images, and the numerical data of figures and charts. With these capabilities, they offer a ready-to-use, easier-to-maintain alternative to complex document understanding pipelines.
The models come in three sizes. The 1B keeps the LightOnOCR-2-1B architecture, while the 0.8B and 4B adopt the Qwen3.5 vision-language architecture, which simplifies integration with existing tools and brings a significant speed-up. All models are released under the Apache 2.0 license for research and commercial use.
Highlights
- π Transcription mode: call the model with an empty prompt and get the full page text, as before. Switching from LightOnOCR-2 requires no change
- π Grounding mode: call it with the
grounding prompt and every block comes back with a label and a bounding box
- πΌοΈ Visual understanding: images get a short description, charts become a table of their data points
- π§ End-to-End: one model instead of a document understanding pipeline, easier to deploy and maintain
- π§Ύ Versatile: handles tables, receipts, forms, charts, multi-column layouts, and math notation
Model Variants
Prompt Modes
The models can be used as before in a transcription-only mode: called with an empty prompt (""; the image only), they output all textual elements of the page as markdown. If you are currently using our previous models, switching to LightOnOCR-3 requires no change, as this is the default behavior.
The new usage mode is to call the models with the grounding prompt. They then output the new vision features alongside the transcribed text. Each block of content is prepended with a placeholder giving its type and its bounding box, in page coordinates normalized to 0β1000:
- Text blocks contain the transcribed content of paragraphs, titles and other text elements.
- Image blocks pair a bounding box with a short description, making visual content accessible to retrieval and question-answering pipelines.
- Chart blocks contain an HTML table of the data points extracted from the figure, turning visual information into structured data.
The placeholder label is one of:
Grounding adds about 25% output tokens over plain transcription (1,433 vs 1,158 tokens per page on average for the 4B). Other instructions are out of distribution: use the empty prompt ("") or grounding.
Usage with Transformers
Note: LightOnOCR-3-0.8B loads with the Qwen3.5 classes (Transformers β₯ 5.2, saved with 5.5.4). It is trained and evaluated with thinking disabled, which is the chat template default.
Usage with vLLM
The LightOnOCR repository on GitHub provides a minimal client, CLI and viewer for the models served with vLLM, plus the code to reproduce our benchmarks.
Rendering and Preprocessing Tips
- Render PDFs at 400 DPI to images using a target longest dimension of 2048px
- Maintain aspect ratio to preserve text geometry
License
Apache License 2.0
Citation