H
Haar
Fast Calculators
In Development

Instant answers for
field engineers

Ultra-fast engineering calculators that load in milliseconds. No frameworks, no bloat—just the tools you need when you need them.

<100ms
Load Time
<50KB
Page Size
100%
Offline

Lightning-fast calculators

Single-purpose tools optimized for instant results

🔢

Hex Converter

Instant conversion between hex, binary, decimal, and ASCII. Perfect for troubleshooting protocol data.

<5KB Coming Soon

CRC Calculator

Calculate CRC-16, CRC-32, and custom polynomials. Essential for Modbus and protocol validation.

<8KB Coming Soon
🔄

Unit Converter

Engineering units for pressure, flow, temperature, power. Optimized for industrial applications.

<12KB Coming Soon
📊

IP Calculator

Subnet masks, CIDR notation, network ranges. Quick network planning for SCADA systems.

<6KB Coming Soon

Ohm's Law

Voltage, current, resistance, power calculations. The basics, done instantly.

<4KB Coming Soon
📡

dB Calculator

Decibel conversions, power ratios, signal levels. RF and audio calculations made simple.

<5KB Coming Soon

Built for speed

Every millisecond matters when you're troubleshooting in the field

Instant Load

No frameworks, no dependencies. Pure vanilla JavaScript means pages load in under 100ms.

📱

Mobile First

Optimized for phones and tablets. Works perfectly on the device already in your pocket.

🔒

Offline Ready

All calculations happen locally. No internet required once the page loads.

🎯

Single Purpose

One tool, one job. No feature bloat, no complicated interfaces—just results.

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