Slice STL to G-code in your browser
A real FDM slicer on the web — printer profiles, supports, infill and a layer-by-layer toolpath preview. Then download the G-code or print it straight to a USB printer. Free, private, never uploaded.
- 1 Drop an STL or 3MF
- 2 See it on your printer’s bed & check the fit
- 3 Tune settings, then slice — follow the live engine progress
- 4 Download the G-code — or print it straight to a USB printer
Printer & material
Quality & infill
Supports & bed adhesion
Speed, placement & advanced
Pause & insert parts
The completed layer stays visible while the next layer waits. Insert the part fully below the highlighted surface, secure magnets so they cannot jump toward the nozzle, then resume from the printer or host.
M0Works only when your Marlin firmware accepts an interactive M0 pause. Resume from the printer screen.M0 may be ignored without an LCD or EMERGENCY_PARSER, and it does not automatically park every printer.
Slice the model first, then choose the exact layer from the preview or here.
Pauses are written into the downloaded G-code immediately before the selected layer. No RESUME command is inserted—the printer or host waits for you.
Start & end G-code (Klipper, custom macros)
Empty = the app’s generic Marlin sequence. Custom start/end G-code replaces it (the slicer still appends the absolute-mode lines the toolpath needs). Placeholders: {nozzle_temperature}, {bed_temperature}, {first_layer_temperature}, {first_layer_bed_temperature}, {layer_height}, {printer_name}, {material_name}, {material_type}, {model_name}. Review it for your printer before the first print.
Capabilities
A desktop-class slicing workflow, online
- Slice STL and 3MF straight to Marlin-flavoured G-code — no install, no account, and the model never leaves your browser.
- 43 editable machine-size presets (Bambu Lab, Prusa, Creality Ender & K1, Elegoo, Voron and more) plus 35 filament presets with matched temperatures.
- Core print settings: layer height, walls and top/bottom skin, infill density with grid/triangle/hexagon patterns, speeds and retraction.
- Automatic supports with overhang threshold and density control, plus skirt, brim or raft bed adhesion.
- Interactive layer-by-layer toolpath preview with a scrubber and travel-move overlay, so you can inspect the print before saving.
- Schedule one or more pauses between exact layers to insert magnets, nuts or bearings, with Marlin, Prusa, Klipper, Duet, OctoPrint and custom command presets.
- Print estimates after slicing: layers, filament length and weight, and estimated print time — generated in background workers with live progress.
- Print straight to a USB-connected printer from the browser over Web Serial (Chrome, Edge or Opera on desktop) — an experimental, ok-acknowledged stream with pause, cancel and emergency stop — or just download the .gcode.
Process
How it works
- Drop your STL or 3MFThe model loads locally and is placed at the centre of your printer’s bed. Pick your printer and filament from the built-in profiles.
- Tune the print settingsLayer height, infill, supports, adhesion, speeds and temperatures — grouped like a desktop slicer, with sane defaults if you just want to go.
- Slice, then download or printInspect the finished toolpath layer by layer. Add pauses before closing layers when a magnet, nut or bearing needs to be inserted, then download the finished .gcode.
Notes
Good to know
- The slicing engine is the self-hosted Kiri:Moto 4.7.1 FDM engine (MIT). Always review the toolpath preview and treat first prints with a new machine preset as test prints.
- Slicing time depends on per-layer contour complexity: simple models slice in seconds, while wide plates with many holes can take several minutes (with live progress).
- G-code is Marlin-flavoured, which most FDM printers accept; custom start/end G-code (including Klipper PRINT_START/PRINT_END macros with placeholders) can be added in the settings.
- Scheduled pauses depend on printer firmware or host support. Choose the matching pause preset and test it on your machine before relying on it. Files with scheduled pauses must be printed from printer/host storage rather than direct browser USB streaming.
- Resin (SLA/MSLA) slicing, multi-material, variable layer height and ironing are not supported.
- Very large meshes are limited by your device’s memory — decimate heavy scans in the STL optimizer first for faster slicing.
- Printing straight from the browser to a USB printer is experimental and needs a Chromium browser (Chrome, Edge or Opera) on desktop — stay with the machine and keep your computer awake. On other browsers, download the .gcode and print from an SD card / USB stick.
FAQ
Questions, answered
Can I really slice a 3D model online without installing a slicer?
Yes. Drop an STL or 3MF, pick a printer profile and press Slice — everything runs locally in your browser in a background Web Worker, and at the end you download standard G-code, or print it straight to a USB-connected printer in Chrome, Edge or Opera. Nothing is uploaded to any server.
Which printers are supported?
There are 43 editable starting presets covering Bambu Lab (A1, P1P, X1 Carbon), Prusa (MK3S/MK4/XL/Mini), Creality (Ender 3 family, CR-10, K1), Elegoo Neptune, Voron, Anycubic and more. A preset supplies bed size, origin, nozzle and conservative speed/retraction defaults; it is not a vendor-tested device profile. Review the G-code and add your printer’s custom start/end sequence when required.
Does it generate supports?
Yes — Kiri:Moto can generate automatic supports with an overhang-angle threshold, density control, and placement either everywhere or only where the support stays connected to the build plate. Tree-specific generation is not available in Kiri:Moto 4.7.1.
Is the G-code safe to print?
The G-code is standard Marlin flavour with your chosen temperatures and speeds, and the layer preview lets you inspect every toolpath before you download or print it. As with any new slicer, watch the first layers of your first print — and prefer the desktop slicer you trust for mission-critical parts.
How long does slicing take?
Typical single objects slice in seconds. Very wide models with many holes per layer can take minutes because each layer’s contours are computed exactly — a progress bar shows the active phase and overall progress, and you can cancel at any time.
My model is huge — what should I do first?
Run it through the STL optimizer to reduce triangles (it preserves shape with quadric simplification), and check it in the printability checker. A lighter, watertight mesh slices dramatically faster and prints more reliably — slicing time is driven by how many contours each layer has, so a heavy 300k-triangle figure can take many minutes while a decimated copy slices in seconds.
Can I print directly from the browser?
Yes, if you use a Chromium browser (Chrome, Edge or Opera) on desktop and the file has no scheduled insert pauses. After slicing, connect your printer over USB and the slicer streams G-code line by line while waiting for each “ok”. Files with scheduled pauses must be downloaded and started from printer storage, OctoPrint or virtual SD because firmware pause commands behave differently during live host streaming.
Can the print pause so I can insert magnets or nuts?
Yes. Slice first, move the layer preview to the last completed layer below the pocket, then add a pause before the next layer. You can add multiple stops, edit the instruction shown at each stop, and choose Marlin M0/M125, Original Prusa M601, Klipper PAUSE, RepRapFirmware M226, OctoPrint @pause or custom G-code. Secure magnets firmly and test the selected pause command on your printer.
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