Pick a tool below. Both run entirely in your browser using the same FCS parser as the FlowVision desktop app.
Your files never leave your computer.
Drop an FCS file, pick the channels you want, download a CSV. The standard way to bridge cytometry data into Excel, R, Python or any tool outside the flow cytometry stack.
Open converter →
Drop an FCS file, see its full metadata: cytometer, acquisition date, channels, every $-keyword in the TEXT segment, and the spillover/compensation matrix with off-diagonal values color-coded.
Open viewer →
Drop an FCS file and run a full integrity check. Catches the structural and keyword problems that make flowCore, R or a strict pipeline reject a file — including the BD FACSDiva "$SPILLOVER size discrepancy" error, with a suggested corrected matrix string.
Open validator →
These tools use the same FCS parser that powers the FlowVision desktop app. Shipping them as free browser utilities does two things at once: gives the cytometry community a few useful one-shot tools that nobody else maintains well, and demonstrates that the underlying engine handles real-world FCS files from every vendor (BD, Cytek, Sony, Beckman Coulter, Stratedigm).
For full analysis — gating, MFI, spectral unmixing, reproducible UMAP, multi-file batch, FlowJo .wsp / Gating-ML 2.0 export — the desktop app is what you want. The browser tools are deliberately small: one job, done well, no install.
Anyone who works with FCS files but does not want to install a full flow cytometry application for a one-shot task:
These browser utilities are deliberately small. They cannot do:
All of the above are in the FlowVision desktop app. The browser tools are the "first contact" — a way to verify your FCS file works with our parser before you decide whether the desktop is worth a trial.
Yes, fully free with no account, no email gate, no rate limit, no watermark. They run as ordinary JavaScript in your browser. The catch (if you want to call it that) is that they exist to demonstrate the FlowVision desktop app — for full gating, MFI statistics, spectral unmixing, batch analysis and FlowJo .wsp export you would buy the desktop. But the free tools work standalone and we maintain them as a service to the cytometry community.
No. Both tools run entirely in your browser via client-side JavaScript. Your file is read into local memory, parsed on your machine, and the output (CSV or JSON) is generated and saved locally. Nothing leaves your computer. You can verify by opening your browser's Network tab while the tool runs — no upload requests.
FCS 2.0, 3.0, 3.1 and 3.2. Files from BD (FACSDiva, Chorus, FACSDiscover S8), Cytek (SpectroFlo on Aurora and Northern Lights), Sony (ID7000, FACSChorus), Beckman Coulter (CytoFLEX, DxFLEX, Kaluza) and Stratedigm all use the same FCS format and parse identically. The browser tools use the same parser as the FlowVision desktop app, which has been tested on production files from each vendor.
Email info@flowvision.io with what you need. Likely candidates already on the roadmap: FCS merger (combine multiple FCS into one), FCS renamer (fix $PnN / $PnS), compensation matrix checker, FCS strip (remove channels). If your specific need fits the in-browser model (file is read locally, no analysis state), it can probably ship in a week or two.
For full analysis (gating, MFI, spectral unmixing, batch, reports) FlowJo / FCS Express / FlowVision desktop are the right tools. The free browser utilities are for one-shot tasks where opening a full analysis tool is overkill: a colleague asks "what channels are in this file?", you need a CSV to drop into Excel for a quick check, you want to verify a file is not corrupted before queuing a batch run. The browser tools are deliberately small — one job, no install, instant.
FlowVision desktop adds gating with auto-fit, spectral unmixing (linear / NNLS / Poisson-WLS), reproducible UMAP, MFI statistics, multi-file batch, Layout report, and FlowJo .wsp + Gating-ML 2.0 export. Windows + macOS, $99 lifetime.
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