# Humidity Calc

> Check humidifier filters.

Canonical page: [https://chrome-stats.com/d/id6797133577](https://chrome-stats.com/d/id6797133577)

## Overview

- **ID:** `id6797133577`
- **Platform:** Apple
- **Type:** Apple app
- **Status:** Available
- **Publisher:** Hiroaki Oosawa
- **Category:** Utilities
- **Version:** 1.0.0
- **Last updated:** 2026-08-31
- **First published:** 2026-08-31
- **Size:** 37 MB
- **Data as of:** 2026-09-13
- **Store listing:** [Apple App Store](https://apps.apple.com/us/app/humidity-calc/id6797133577)
- **Website:** [https://ratel-okottel.com](https://ratel-okottel.com/)
- **Privacy policy:** [https://ratel-okottel.com/privacy/](https://ratel-okottel.com/privacy/)

## Description

Calculates theoretical indoor humidity from RH and temperature. Converts RH to absolute humidity to compare with measured values and track performance/filter efficiency.

【Calculate Theoretical Relative Humidity】

A humidity calculation app for managing indoor humidity and checking humidifier performance.

Calculate the theoretical indoor relative humidity from the outdoor temperature, outdoor relative humidity, and your indoor temperature.

By comparing the calculated value with your hygrometer reading, you can estimate humidification performance and determine when a humidifier filter may need replacement.

This app does not measure humidity.

【Key Features】

• Calculate theoretical indoor relative humidity
• Compare calculated and measured humidity
• Check humidifier performance
• Estimate humidifier filter deterioration and replacement timing
• Support daily indoor humidity management

【Recommended For】

• Users of evaporative humidifiers
• Anyone who wants to check humidifier performance
• Anyone who wants to know when to replace a humidifier filter
• People managing indoor humidity during dry seasons
• Anyone who wants to compare theoretical and measured humidity

【What Is Theoretical Relative Humidity?】

This app calculates the theoretical indoor relative humidity by converting outdoor relative humidity based on the amount of water vapor and applying the indoor temperature.

Comparing the theoretical value with your hygrometer reading helps you evaluate humidifier performance and estimate whether the filter has lost efficiency.

Ideal for users who want a simple way to monitor indoor humidity and maintain humidifier performance.

## Rankings

- #2,193,829 — Overall

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Source: [Chrome-Stats](https://chrome-stats.com/d/id6797133577)