MST·tools
JavaScript is required for the inspector. It parses your file locally in your browser; the documented method is at the bottom of this page.
Free · open-source · runs 100% in your browser

Local GDSII Inspector

Drop a .gds file to read its top cell, die size, layer list, cell hierarchy and element counts — then generate a non-confidential RFQ summary. Built to prove our promise: we never take your layout. Here, it doesn't even leave your machine.

🔒 100% local. No upload, no server, no backend — parsed in a Web Worker on your device.

Representative die largest top cell

Library

Elements

Layers

LayerDatatypeElements

Cell hierarchy

Non-confidential RFQ summary

Only metadata below — die size, counts, units. No geometry, no polygons, no IP. Send it (or the deep-link) to start a partner-confirmed MPW quote.


      

        Start MPW RFQ with this die size →
        
        
        
      

    

  


  

    How it works (and what stays private)
    

      
Nothing is uploaded

      Your file is read with FileReader into memory and parsed by an inline Web Worker on your own device. There is no backend and no network request with your data. The "RFQ" buttons only build a link/text from the metadata (die size + counts) you see on screen.
      
What it reads

      It walks the GDSII record stream (big-endian), decodes the UNITS record's metres-per-database-unit to get true micrometres, collects every cell (STRNAME), every reference (SREF/AREF) to build the hierarchy, and every (LAYER, DATATYPE) pair. The die size is the bounding box of the top cell, computed recursively through all instances — each instance transformed by its reflection → magnification → rotation → translation, with arrays (AREF) handled in closed form. Reference cycles and missing cells are detected and skipped, never hung on.
      
Approximations

      The die box is an axis-aligned bounding box (slightly conservative for rotated layouts); PATH width end-caps are approximated to ±½ width; TEXT labels are excluded from die size (they can sit outside the layout). Random things a real quote depends on — process, mask grade, packaging — aren't in a GDS and aren't inferred here.
      
Privacy & licence

      Open-source (MIT). One self-contained HTML file. Read it, fork it, run it offline. This mirrors how we work: at the RFQ stage we take a high-level brief, not your GDS.