Open RAW files in your browser
The results a circuit simulator writes, from ngspice, LTspice, Xyce and Qucs. Open one right here, every voltage and current as a curve, with no simulator. Nothing leaves your device.
Or drop it anywhere on this page
What you'll see
Your results open with each voltage and current as a curve, along the time, the swept value or the frequency.
- Every node and current • Transient, DC, AC and stepped runs
- Two cursors • Each curve at both, and its lowest, highest, mean and RMS between
- Find a node or a current by its name
- Export • PNG, and the points as CSV
About RAW
Berkeley's SPICE3 wrote its results as a raw file for its plotter, Nutmeg, and its descendants still do: ngspice, LTspice, Xyce, Qucs-S and KiCad's simulator all write .raw files, binary or as text.
A raw file has a header of lines, its title, the analysis, its flags, the number of points and each variable's name and kind, a voltage, a current, the time or the frequency, then the points, a value for each variable at each step: doubles, LTspice's floats, or complex numbers for an AC analysis. A run stepped through a parameter keeps its steps one after another.
Filepeek reads it in your browser and draws every variable as a curve along the time for a transient, the swept value for a DC sweep, or the frequency on a log scale for an AC analysis, its magnitude in dB with its phase. Each step of a stepped run is a group of its own. Drag or pinch to move and zoom, put two cursors to read each curve at both with its lowest, highest, mean and RMS between them, find a node by its name, and save the view as PNG or the points as CSV.
SPICE raw file
.raw
Format
- MIME type
- application/x-spice-raw
- Made by
- UC Berkeley's SPICE3
Inside the file
- Header
- The title, the analysis and each variable
- Variables
- Voltages, currents, the time or the frequency
- Points
- Doubles, floats or complex numbers
- Steps
- A stepped run's steps one after another
Opens in every browser
Filepeek opens SPICE raw files in Chrome, Edge, Firefox and Safari, binary or text, LTspice's too. On their own, browsers only download them.
- YouChromeOpens through Filepeek
- YouEdgeOpens through Filepeek
- YouFirefoxOpens through Filepeek
- YouSafariOpens through Filepeek
Apps that open RAW
- WindowsLTspice or ngspice, free
- MacLTspice, free
- iPhone and iPadNo app opens it
- AndroidNo app opens it
Questions
How do I open a .raw file without LTspice?
Drop it on this page or choose Peek a RAW. Every voltage and current opens as a curve in your browser, on a phone too.
How do I read a voltage at a given time?
Click the curve's lane to put cursor A there, and each signal shows its value at A by its name. Shift-click puts cursor B, and a signal's card shows its value at both and its lowest, highest, mean and RMS between them.
Does it show an AC analysis as a Bode plot?
Yes. Each node shows as its magnitude in dB and its phase in degrees, along the frequency on a log scale.
What if my .raw file isn't a simulation?
A camera's raw photo or a raw disk image can be named .raw too. Filepeek tells SPICE's by the header it starts with, so a photo still opens as a photo and a disk image as its files.
Can I turn the results into CSV?
Yes. Choose Export, then Save the values, for the points between the cursors, or in the view when no cursors are put, a column for each variable.