Technical Utilities for Power Users.

A collection of 15 free, high-performance browser tools for developers, designers, and data analysts — hex and byte converters, image processing utilities, a 2D-to-3D CAD/STL exporter, generative geometry tools, and lightweight mechanics/aerodynamics simulators. Every tool runs entirely client-side: nothing you upload or type is sent to a server.

Visual

MilliCAD

Simple, easy-to-use 2D-to-3D CAD tool for making printable STL files.

#stl#cad
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Video

GIFSpeed-0

Speed up or slow down a GIF's playback while keeping high-fidelity color and frame quality.

#gif#speed
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Developer

HexToAscii

Decode hexadecimal byte strings into readable ASCII text in real time.

#hex#ascii
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Developer

HEXTxt

Two-way text/hex encoder with endianness and delimiter controls.

#text#hex
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Data

NumericStats

Extract numbers from raw text and get instant sum, average, count, and range.

#math#numbers
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Visual

HilbertsSquiggle

Generates Hilbert space-filling curves at adjustable recursion depth.

#math#hilbert
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Image

JPGqualityADJ

Live JPEG compression control to balance file size against visual quality.

#jpg#compression
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Image

PNG Color Swap

Replace a specific color across a PNG while preserving shading and edges.

#png#color
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Visual

TXT to Image Gen

Render styled text onto a canvas and export it as an image.

#text#image
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Image

PNG color Remover

Make a chosen background color transparent with adjustable tolerance.

#png#transparency
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Visual

Fractal Twiggg

Recursive procedural generator for branching fractal tree structures.

#fractal#recursive
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Visual

Cargo Packing Simulator

3D load-planning for a trailer, cargo van, container, or storage unit.

#container#moving
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Visual

Propeller Simulator

Models how pitch, diameter, and RPM affect propeller thrust and efficiency.

#propeller#mechanics
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Visual

Mechanical Simulator

Lightweight sandbox for experimenting with shapes, forces, and basic physics.

#physics#mechanics
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Visual

Wind Tunnel Simulator

Estimates drag and lift coefficients for a shape you configure.

#wind#aerodynamics
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About SimpleToolHub

SimpleToolHub is a free collection of single-page browser utilities built for developers, designers, and hobbyists who need a specific job done without installing software or creating an account. Every tool listed above is self-contained: open it, do the task, and leave. There's no sign-up, no file storage, and no server round-trip for your data — conversions, image processing, and simulations all run locally in your browser using JavaScript and the Canvas/WebGL APIs.

The catalog spans a few categories: developer utilities for converting between hex and text (HexToAscii, HEXTxt) and analyzing numeric data (NumericStats); image tools for compression, background removal, and color replacement (JPGqualityADJ, PNG Color Swap, PNG color Remover); generative/visual tools for fractal and space-filling geometry (Fractal Twiggg, HilbertsSquiggle, TXT to Image Gen); and engineering-flavored simulators for load planning, mechanics, propellers, and aerodynamics (Cargo Packing Simulator, MechSim, Propeller Simulator, Wind Tunnel Simulator, MilliCAD).

Click any tool above for a full description, step-by-step usage instructions, and answers to common questions on that tool's own page.