README.md

metadata

title: CUDA Thread Visualizer
colorFrom: green
colorTo: blue
sdk: static
pinned: false
license: mit
short_description: A 3D visualizer for CUDA grid/block/thread hierarchy

CUDA Thread Visualizer

An interactive 3D visualizer that helps you understand how CUDA organizes threads into blocks and grids. See exactly how blockIdx, threadIdx, blockDim, and gridDim map to each individual thread — and how global indices are computed.

Built as a single HTML file with zero dependencies. Just open it in a browser.

Why

When learning CUDA programming, one of the first hurdles is understanding the thread hierarchy: how a kernel launch like kernel<<<dim3(2,2,1), dim3(4,4,1)>>>() maps to actual thread coordinates. This tool makes that mapping visual and interactive.

Features

• 3D visualization of every thread as a colored cube, with blocks distinguished by color and spacing
• Full dim3 control — configure gridDim(x,y,z) and blockDim(x,y,z) with real-time updates
• Click any thread to inspect its blockIdx, threadIdx, and see the global index formula using CUDA built-in variables
• NVIDIA-standard coordinate system — X→right, Y→down, Z→depth, matching the official CUDA Programming Guide
• Auto-fit zoom — the view automatically scales to fit any grid configuration
• Presets for common patterns: 1D, 2D, 3D, and GEMM-style layouts
• Live kernel launch bar showing the corresponding kernel<<<grid, block>>>() syntax
• Axis compass that stays on screen so you always know the orientation
• Touch support — works on mobile with pinch-to-zoom and drag-to-rotate

Controls

Action	Mouse	Touch
Rotate	Left drag	One-finger drag
Pan	Right drag	—
Zoom	Scroll wheel	Two-finger pinch
Select thread	Click	Tap

License

MIT