Find the output for your firmware
Begin with one complete height grid from your printer's console or an existing export. Check the instructions for your printer and installed firmware before sending commands. Bed Mesh reads measurements; it does not connect to your printer or start a probing routine.
Marlin
Use the grid from your documented mesh routine. G29 behaves differently across Marlin's configured levelling systems and can initiate probing. Identify the mode in your build before choosing commands. See the official Marlin G29 documentation.
Prusa
The documented Prusa Firmware G81 command reports mesh status and, when active, the bed profile. This command reference does not cover every newer Prusa firmware family; confirm your model's documentation. See Prusa's firmware-specific command reference.
Klipper
BED_MESH_OUTPUT reports the current mesh state. Copy the numeric height matrix you want to inspect. The generated-point coordinate table from PGP=1 describes positions, rather than a matrix of measured heights. See Klipper's mesh output documentation.
Keep the values intact
Bed Mesh accepts supported Marlin and Prusa console grids, Klipper numeric matrices, plain rectangular grids, numeric CSV, and JSON arrays of numeric rows. Keep every measurement in its original row and column. A simple JSON input looks like this:
[[0.02, -0.01, -0.04],
[0.01, -0.02, -0.05],
[0.00, -0.01, -0.03]]Use millimetres and decimal points. Preserve minus signs and precision. Each row must contain the same number of heights. Missing or invalid points need resolving at the source; replacing them with zero would introduce a measurement you did not take.
Load it and check the result
Paste into Input, or use Import file for a text, CSV, or JSON file. Select Visualize, check the detected grid size, and compare a few cells in View measured values with your source. A single row or column can be inspected as a heatmap; a 3D surface needs both dimensions.
If parsing fails, read the message and check for incomplete rows or unrelated numeric tables mixed into the output. Keep a copy of the source while cleaning the input.
Keep a useful record
No account is needed. The visualizer processes your grid locally and saves the workspace in this browser. Export CSV for a separate copy, and keep the original console output with the date, bed temperature, and probing setup. Those details make your next comparison much more useful.