Mathypad

A smart TUI calculator that understands units and makes complex calculations simple.

What is it?

Mathypad is like a notepad where you can write math expressions with real-world units, and it automatically calculates results for you. Think "Google calculator" or Soulver but for your terminal, with support for data sizes, time, and API performance metrics.

Quick Start

# Cargo install
cargo install mathypad

# Clone and run
git clone https://github.com/pato/mathypad.git
cd mathypad
cargo build --release
cargo install --path .

# Or use it directly from command line
mathypad -- "100 QPS * 1 hour"           # → 360,000 query
mathypad -- "5 GB to GiB"                # → 4.657 GiB
mathypad -- "1 TB/s * 30 minutes"        # → 1,800 TB

Why You'll Love It

Smart Unit Handling

No more mental math converting between GB and GiB, or calculating how many requests your API serves per day:

50 GiB/s * 1 hour                    → 180,000 GiB
100 QPS to requests per day          → 8,640,000 req
2 TB + 500 GB                        → 2,500 GB
1 PB to TiB                          → 909,494.702 TiB

Real-World Problem Solving

Perfect for DevOps, data engineering, and capacity planning:

# How much storage for 6 months of logs?
100 MB/day * 180 days                → 18,000 MB

# API capacity planning
500 QPS * 1 year                     → 15,778,800,000 query

# Data transfer estimates  
10 Gbps to TB/hour                   → 4.5 TB/h

# Storage consolidation
5 TB + 2.5 TB + 1024 GiB             → 8.524 TB

Interactive or One-Shot

Use it like a notepad with live results, or fire quick calculations from your terminal:

Interactive Mode (with vim motions):

$ mathypad
┌─ Mathypad ────────────────────┬─ Results ─────────────┐
│   1 │ 100 QPS * 8 hours       │   1 │ 2,880,000 query │
│   2 │ line1 / 1000            │   2 │ 2,880 query     │
│   3 │ 50 GB to GiB            │   3 │ 46.566 GiB      │
│   4 │                         │   4 │                 │
└─ -- NORMAL -- ───────────────┴───────────────────────┘

• ESC → Normal mode (hjkl navigation, indicator at bottom)
• i/a/o → Insert mode for editing
• Ctrl+C/Ctrl+Q → Quit

Command Line:

mathypad -- "1.5 EB / 100 Gbps"         → 33.333 h

What It Handles

Data Units

• Decimal: B, KB, MB, GB, TB, PB, EB
• Binary: KiB, MiB, GiB, TiB, PiB, EiB
• Rates: All the above + /s (e.g., GB/s, TiB/s)

Performance Metrics

• QPS: queries per second, minute, hour
• Request rates: req/s, req/min, requests/hour
• Load calculations: QPS × time = total requests

Time

• Seconds, minutes, hours, days
• Mix and match: 90 minutes + 1.5 hours = 240 min

Complex Operations Made Simple

Data Center Planning

# Total monthly bandwidth
1 PB/day * 30 days                   → 30 PB

# Storage requirement with replication  
100 TB * 3 replicas + 20% overhead   → 360 TB

# Network utilization
50 Gbps * 0.8 utilization to TB/day  → 432 TB/day

API Performance Analysis

# Peak load calculation
1000 QPS * 1.5 peak_multiplier       → 1,500 QPS

# Monthly request volume
250 QPS * 30 days                    → 648,000,000 query

# Load balancer distribution
5000 QPS / 10 servers                → 500 QPS

Mixed Unit Calculations

# Different storage types
2 TiB SSD + 8 TB HDD                 → 10.196 TB

# Cross-base conversions
1000 GB * 0.931 to GiB               → 931 GiB

# Rate × time calculations
100 MiB/s * 2 hours to GiB           → 703.125 GiB

Conversion Chains

# Multi-step conversions
24 MiB * 32 servers in GB            → 0.805 GB
5000 queries / 10 minutes to QPS     → 8.333 QPS
(1 TiB + 500 GiB) / 8 hours          → 0.052 TiB/s

Advanced Features

Line References

Reference previous calculations in your notepad:

Line 1: 100 TB
Line 2: line1 * 0.8                  → 80 TB
Line 3: line2 to TiB                 → 72.760 TiB

Smart Parsing

It figures out what you mean:

Transfer: 5 PB in 2 days             → 28.935 TB/s
API load during peak: 2000 QPS       → 2,000 QPS
Storage needed: 500 GB * 12 months    → 6,000 GB

Flexible Syntax

Use "to" or "in" for conversions:

1 GB to MiB                          → 953.674 MiB
100 TB * 3 in PB                     → 0.3 PB

Installation

Requires Rust:

git clone https://github.com/pato/mathypad.git
cd mathypad
cargo build --release

Or run directly:

mathypad                         # Interactive mode
mathypad -- "your calculation"   # One-shot mode

Use Cases

• DevOps: Storage capacity planning, bandwidth calculations
• Data Engineering: Dataset size estimates, transfer time calculations
• API Design: Rate limiting, capacity planning, load testing
• System Administration: Resource allocation, performance monitoring
• General Computing: Any calculation involving data sizes or rates

Why Not Just Use a Regular Calculator?

# Traditional way:
# 1. Convert 1 PB to bytes: 1,000,000,000,000,000
# 2. Divide by bytes per GiB: 1,000,000,000,000,000 ÷ 1,073,741,824
# 3. Get: 931,322.574615479

# Mathypad way:
1 PB to GiB                          → 931,322.575 GiB

Much better, right?

Developed using AI 🤖

This was developed using Claude Code (with 3.5 Haiku and Sonnet 4) for a grand total of $25.60

Every commit has alongside with it the prompt I used that generated the contents of the commit (with the exception of commits marked as no ai, but there was no code that wasn't written by the model).

> /cost
  ⎿  Total cost:            $25.60
     Total duration (API):  1h 45m 33.9s
     Total duration (wall): 23h 21m 24.6s
     Total code changes:    3518 lines added, 610 lines removed
     Token usage by model:
         claude-3-5-haiku:  405.9k input, 21.2k output, 0 cache read, 0 cache write
            claude-sonnet:  2.4k input, 213.9k output, 47.4m cache read, 2.1m cache write