# Tolerance Helper — ISO tolerance size calculator

> ISO tolerance size calculator (iPhone/iPad app by Dmitriy Trofimov.)

- Source: https://appshunter.io/ios/app/tolerance-helper/id6745212628 (this page in markdown: same URL + `.md`)
- Developer: [Dmitriy Trofimov](https://appshunter.io/developer/1598378710)
- Category: Reference
- Price: Free
- Age rating: 4+
- Requires: iOS 12.0 · 29 MB
- Languages: American English
- Released: 2025-04-30
- Data updated: 2026-09-09
- User reviews in markdown: https://appshunter.io/ios/app/tolerance-helper/id6745212628/reviews.md

## What is Tolerance Helper?

Tolerance Calculator
Tolerance Calculator is a comprehensive engineering reference tool for mechanical design and precision manufacturing professionals. This app simplifies the process of calculating dimensions with ISO standard tolerances for both holes and shafts.
Key Features
Comprehensive Tolerance Reference

Complete reference table of engineering tolerances
Support for both hole and shaft designations (e.g., H7, h7)
Spans all standard dimensional intervals

Easy Tolerance Calculation

Calculate minimum, maximum, and average dimensions
Enter a nominal dimension and view all tolerance limits instantly
Results displayed clearly with color-coded indicators
Copy results to clipboard with a single tap

Powerful Search and Filtering

Quick search for specific tolerance designations
Filter by hole or shaft tolerances
Recent searches history for faster access
Customizable tolerance filter to show only designations you need

Multi-unit Support

View tolerances in millimeters (mm)
Convert to inches (in) with proper precision
Convert to micrometers (μm) for precision work

User-Friendly Interface

Intuitive navigation with tolerance table
Clean, engineering-focused design
Clear color coding: blue for holes, green for shafts
Clickable cells for instant calculations

Accessibility Features

Dark mode support for low-light environments
Responsive layout for phones and tablets
Support for both portrait and landscape orientations

Localization

English and Russian language support
International engineering symbols
Professionally translated interface

Perfect For

Mechanical engineers
CNC machinists
Manufacturing technicians
Quality control specialists
Engineering students
Technical designers
Precision fabricators

Tolerance Calculator is the essential pocket reference for anyone working with precision mechanical parts. Calculate proper fits and clearances accurately without the need for paper tables or complex formulas.
Download now and simplify your engineering calculations!


## Version history (last 2 releases)

### 1.6.0 — 2025-05-07

Improved column organization: Hole and shaft tolerances are now arranged in alternating pairs (H1, h1, H2, h2...) for easier comparison

### 1.0 — 2025-04-30

No release notes.

## Apps similar to Tolerance Helper

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [CNC Lathe Calculator & Program](https://appshunter.io/ios/app/cnc-lathe-calculator-and-program/id6758656996) | 5.0 (2) | Free | Reference |
| [Bearing](https://appshunter.io/ios/app/bearing/id542000172) | — | Free | Reference |

## More apps by Dmitriy Trofimov

- [Triangle Angles Calculator](https://appshunter.io/ios/app/triangle-angles-calculator/id1598378708)
- [ThreadFon Multi-Thread Calc](https://appshunter.io/ios/app/threadfon-multi-thread-calc/id1602169811)
- [Castoro — Sheet Cutting](https://appshunter.io/ios/app/castoro-sheet-cutting/id6757387540)

All apps by Dmitriy Trofimov: https://appshunter.io/developer/1598378710

## Related topics

[mekanicapp](https://appshunter.io/ios/topics/mekanicapp)

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-09-09.*