ANSI Fit & Thread

🚀 Speed up your engineering designs and machining setups! ANSI Fit & Thread is an offline, precision calculator tailored for mechanical engineers, CNC operators, machinists, designers, and students.

Calculate standard tolerances, clearance/interference limits, thread geometries, and tap drill sizes instantly using imperial ANSI standards.

Key Features:

1. ANSI B4.1 Fits & Tolerances Calculator
• Enter nominal sizes (from 0.01" up to 19.69") and get exact limit values.
• Supports standard ANSI tolerance classes including:
- Running/Sliding Fits (RC)
- Locational Clearance Fits (LC)
- Transitional Fits (LT)
- Locational Interference Fits (LN)
- Force/Shrink Fits (FN)
• High-fidelity engineering diagrams showing hole/shaft envelopes.
• Displays Max/Min clearances, interferences, and Allowance.

2. Unified Thread Pitch Calculator
• Look up standard ANSI/ASME thread details (UNC, UNF series).
• Instantly retrieves Major Diameter, TPI (Threads Per Inch), Pitch, Pitch Diameter, and Minor Diameter.
• Shaded 60° thread profile visual diagrams showing reference boundaries.

3. Tap Drill Size Calculator
• Instantly calculates the theoretical ideal tap drill size.
• Recommends the best standard drill bits (Fractional, Letter, Number, or Metric sizes) for target thread engagements.
• Displays real-time thread engagement percentage progress charts.
• Provides alternative drill sizes with precise decimal equivalents.
• Tapped hole engineering cross-hatch diagrams with clear annotations.

4. History Management & Export
• Auto-saves recent calculation records to a rolling history list.
• Pin favorite measurements so they never expire.
• Search through history by custom names, sizes, or parameters.
• Export history to a standard CSV file for spreadsheets and reports.
• Native Android share sheet support with clean diagram images and text descriptions.

Why Choose ANSI Fit & Thread?
• 100% Offline: No internet connection required. Perfect for workshops and factories.
• Privacy First: Zero accounts, zero analytics tracking on calculation details. Your data stays on your device.
• Single-Screen UX: Smooth tab navigation with clear, readable monospaced layouts—no nested menus or popups.
• Clean M3 Design: Optimized light and dark themes with Machinist Steel styling.

Disclaimer: This application is a curated lookup and formula reference tool. For safety-critical or production tolerancing designs, always cross-reference outputs with official ANSI/ASME standards.