Is this OSRA online alternative free? Do I need to sign up?

Yes. This tool is free to use online for personal and educational use, and you can start recognition directly in the browser without creating an account.

Can I paste a screenshot or image URL instead of uploading a file?

Yes. This page supports local file upload, clipboard screenshot paste, and direct image URL import in one workflow.

How do I get a 3D molecule after image recognition?

After image recognition returns SMILES, the page can query PubChem or NCI/CADD to fetch standardized 3D coordinates and display an interactive 3D molecule preview.

How can I improve recognition accuracy for complex images?

Use high-resolution, high-contrast images with complete bonds and labels. Avoid heavy blur, partial cropping, and noisy backgrounds to improve OCR quality.

Can I export recognition results?

Yes. You can copy SMILES and download .smi or .mol files for downstream editing, simulation, and teaching workflows.

Free OSRA Online Alternative: Chemical Image to SMILES + 3D Molecule Viewer

Upload files, paste screenshots, or image URLs. No sign-up required to convert structures into SMILES, export MOL, and inspect interactive 3D molecules in one workflow.

Free online recognition directly in the browser.
Supports file upload, screenshot paste, and image URL import.
After recognition: 2D/3D preview, SMILES copy, and .smi/.mol export.

OCSROSRAImage to SMILESDECIMER3D Molecule Viewer

Start Free Recognition Continue to 3D Animation Editor

Step 1: Import Chemical Structure Image

Choose file upload, screenshot paste, or direct image URL import.

Select Import Method

Supports hand-drawn, screenshots, textbook photos, and various chemical molecule images

Live Preview (2D + 3D)

RDKit 2D Diagram

2D preview will appear after recognition

2D Planar Structure in 3D View

Drag to rotate, scroll to zoom

3D preview appears after recognition

How to Convert Chemical Image to SMILES and 3D Molecule (OCSR Workflow)

Import image: upload file, paste screenshot, or paste image URL.
Start recognition to get SMILES and verify with the 2D structure preview.
The system auto-tries PubChem first, then falls back to NCI/CADD for 3D coordinates.
Export results by copying SMILES or downloading .smi/.mol, then continue editing.

Lower Bounce

Recognition, preview, and export are completed in one page.

Higher Usability

Supports file upload, screenshot paste, and URL import.

Better Conversion

One-click transition to 2D/3D editors after recognition.

FAQ: OSRA / OCSR Questions

What is the difference between OSRA and OCSR?

OSRA (Optical Structure Recognition Application) is a specific open-source tool maintained by NCI. OCSR (Optical Chemical Structure Recognition) is the broader technical task/domain.

Is this tool free? Do I need to sign up?

Yes. The online workflow is free for personal and educational use, and no account is required to start recognition.

Why is this page easier than a traditional OSRA-only page?

This page supports local upload, screenshot paste, and URL input, then gives 2D + 3D previews, SMILES copy, and MOL download in one workflow.

How is the 3D structure generated after recognition?

The image is recognized into SMILES first, then standard 3D coordinates are fetched from PubChem or NCI/CADD and rendered as an interactive model.

Why do some images produce poor recognition?

Low resolution, incomplete cropping, complex stereochemistry labels, and noise all reduce accuracy. Use clear, high-contrast structure diagrams.

Can I export the recognition result?

Yes. You can copy SMILES and export .smi/.mol files for downstream modeling, teaching, or editing.

External Resources and References

Tip: If your goal is quick structure extraction and animation workflow, use the OCSR flow on this page first; then compare with external OSRA when needed.

Continue with: Molecule Library · PubChem · 3D Editor