GDS (.gds, GDSII — Graphic Data System II) is the industry-standard binary format for integrated circuit layout data, originally developed by Calma in the 1970s. It stores polygon geometry organized by layer, along with cell hierarchies, text labels and layout structure.

OASIS (.oas, .oasis, Open Artwork System Interchange Standard) is the modern successor to GDSII, standardized by SEMI in 2004. It uses efficient compression (run-length encoding, repetitions) to achieve much smaller file sizes than GDSII while preserving the same geometric data.

Are my GDS files uploaded?

No. Layout files you open from your device stay on your device and are parsed locally. Only the public sample file is requested from the server.

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GDS Viewer

Free online GDS viewer. Open and preview chip layout files (.gds, .oas, .oasis) directly in your browser — no upload, no software.

.gds.oas.oasis

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About this file format

GDS (.gds, GDSII — Graphic Data System II), developed by Calma in the late 1970s, is the enduring industry standard for integrated circuit layout data exchange. Despite its age, GDSII is used by every semiconductor foundry (TSMC, Intel, Samsung, GlobalFoundries) and every EDA tool (Cadence, Synopsys, Mentor). OASIS (.oas, SEMI standard, 2004) is the modern compressed replacement, typically 10-50x smaller than equivalent GDSII files.

GDS Viewer

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