Frequently asked questions
Where your file goes, cost, supported browsers and phones, scanned drawings, analysis accuracy, editing and more — common questions about Schematic Viewer.
Files and security
Is my schematic uploaded to a server?
No. The PDF you choose is read and analyzed only inside your browser; it is never sent to or stored on a server. Neither the file's contents, its name nor the analysis results are logged. You can confirm this yourself by watching the Network tab of your browser's developer tools while opening a file. Details are in the privacy policy and the file-handling policy in the terms of use.
When is an opened file deleted?
It lives only in the memory of your browser tab and is gone when you open another PDF, reload the page or close the tab. Nothing is kept in browser storage.
Can I open confidential company schematics?
Because the file never leaves your device, viewing is technically safe. If your company has rules about external web tools, follow them first. When reporting a problem, please don't send confidential drawings — describe the symptom or share a public drawing that shows it.
Requirements
Does it cost anything? Do I need an account?
It is free and needs no sign-up or login. Ads may be shown on the site to cover running costs.
Which browsers are supported?
Current versions of Chrome, Edge, Safari and Firefox. Nothing to install. Very old browsers may fail to read the PDF or draw it.
Does it work on a phone?
Yes. Pinch with two fingers to zoom and drag with one to pan. In portrait the list becomes a bottom panel, in landscape a side panel. Large drawings are still easier on a wide screen. See "On a phone" in the guide.
Can it open large files?
There is no set size limit, but everything runs on your device, so long or complex schematics take longer to analyze and can be slow on phones with little memory.
Analysis results
Can scanned drawings be analyzed?
You can view them, but connections can't be analyzed: in a scan, lines and letters are one picture with nothing to read. Use a PDF exported from the schematic program (see Supported files).
Are the results always correct?
No. Schematic Viewer infers connections from the lines and text drawn in the PDF; it does not read the original design's netlist. It can mistake a part outline for a wire or miss a label. Use it to review and explore, and confirm important decisions — production or repair — against the original design files and the CAD netlist.
Why do labels with the same name show up separately?
A label away from its wire or overlapping other text may not be recognized. Searching for the name still finds every occurrence. If it keeps happening, let us know via the contact page.
What is a "net"?
A group of wires and pins that are electrically connected. Labelled nets are listed by name; unlabelled ones can be inspected by clicking their wires on the drawing. If the symbols are new to you, see Reading schematics.
Features
Can I edit the schematic or add notes?
No — Schematic Viewer is view-only. You can save the net and part lists as CSV and work with them in a spreadsheet.
Can it open KiCad or Altium source files?
Only PDFs for now. Export a PDF from your schematic program first.
Is it available in English?
Yes. Switch between Korean and English with the language buttons (한국어 / EN) at the top; your choice is remembered for next time.
Can I try it first?
Open the example schematic right away, and follow along with the step-by-step example.