Practical tools
Simple tools for everyday and technical work: unit converter (metric and imperial), strong passwords, QR codes, GUID/UUID, text encoding, number bases and Unix timestamps.
Available Tools
Unit converter
Temperature, length, weight, volume and more, between metric and the imperial units still common in Canada.
Password generator
Strong random passwords generated locally with your browser’s cryptography, with a strength indicator.
QR code generator
QR codes for a link or any text, downloadable as an image for a poster, card or menu.
GUID / UUID generator
Version 4 UUIDs, ready to copy in one click.
Text encoder
Base64, URL and HTML entity encoding and decoding.
Number base converter
Convert between binary, octal, decimal and hexadecimal.
Unix timestamp converter
Unix timestamps (seconds or milliseconds) to readable dates and back, with time zones.
Practical tools guide
These tools solve small, concrete problems: converting a recipe or a measurement between metric and imperial, creating a strong password, sharing a link with a QR code or troubleshooting a technical file. Here is what you need to know to use them well.
Measurement systems around the world
Two measurement systems dominate worldwide:
- The metric system (SI): used by most countries, based on multiples of 10 (meter, gram, liter)
- The imperial system: used primarily in the United States (foot, pound, gallon)
The metric system has been officially adopted by most countries since the 19th century due to its simplicity. Conversions are intuitive: 1 km = 1000 m, 1 kg = 1000 g. The imperial system, inherited from the British Empire, uses less regular conversion factors (12 inches = 1 foot, 16 ounces = 1 pound).
Canada has officially used the metric system since the 1970s, but imperial units remain common in daily life: height in feet and inches, weight in pounds, building material dimensions.
Temperature conversions
Temperature is measured primarily with three scales:
- Celsius (°C): used worldwide, where 0° = water's freezing point and 100° = boiling point
- Fahrenheit (°F): used in the United States, where 32° = freezing and 212° = boiling
- Kelvin (K): absolute scientific scale, where 0 K = absolute zero (-273.15°C)
Conversion formulas:
- °F = (°C × 9/5) + 32
- °C = (°F - 32) × 5/9
- K = °C + 273.15
Tip: 28°C ≈ 82°F is a good summer temperature, while -40° is identical in Celsius and Fahrenheit.
Length conversions
Lengths range from microscopic to cosmic. Here are the most useful conversions:
Metric:
- 1 kilometer (km) = 1000 meters (m)
- 1 meter = 100 centimeters (cm)
- 1 centimeter = 10 millimeters (mm)
Imperial:
- 1 mile = 1.609 km
- 1 yard = 0.914 m
- 1 foot = 30.48 cm = 12 inches
- 1 inch = 2.54 cm
To remember: your thumb measures about 2.5 cm, a normal step is about 75 cm, and a football field is about 100 m.
Weight and mass conversions
Weight and mass, although technically different, are often used interchangeably in daily life:
Metric:
- 1 metric ton = 1000 kilograms (kg)
- 1 kilogram = 1000 grams (g)
- 1 gram = 1000 milligrams (mg)
Imperial:
- 1 pound (lb) = 453.6 g ≈ 0.45 kg
- 1 ounce (oz) = 28.35 g
- 1 stone = 14 pounds = 6.35 kg (used in the UK)
For cooking: 1 cup of flour ≈ 125 g, 1 cup of sugar ≈ 200 g. These equivalents vary depending on the ingredient's density.
Volume conversions
Volume measures the space occupied by a liquid or solid:
Metric:
- 1 liter (L) = 1000 milliliters (mL) = 1 dm³
- 1 cubic meter (m³) = 1000 liters
Imperial (note US/UK differences):
- 1 US gallon = 3.785 L
- 1 UK gallon = 4.546 L
- 1 US quart = 0.946 L
- 1 US pint = 0.473 L
- 1 US cup = 236.6 mL ≈ 240 mL
- 1 tablespoon = 15 mL
- 1 teaspoon = 5 mL
In cooking, American and British measurements differ—be careful with international recipes.
The anatomy of a strong password
A secure password is your first line of defense. The characteristics of a good password:
- Length: minimum 12 characters, ideally 16 or more
- Complexity: mix of uppercase, lowercase, numbers, and symbols
- Uniqueness: a different password for each account
- Unpredictability: avoid dictionary words, birth dates, names
Entropy measures password strength. A 12-character password with all character types has about 78 bits of entropy, requiring billions of years to crack by brute force.
Our generator creates cryptographically random passwords that are impossible to guess.
GUID and UUID: unique identifiers
GUIDs (Globally Unique Identifiers) and UUIDs (Universally Unique Identifiers) are standardized 128-bit identifiers used to uniquely identify resources.
Format: 8-4-4-4-12 hexadecimal characters Example: 550e8400-e29b-41d4-a716-446655440000
Common versions:
- UUID v1: based on timestamp and MAC address
- UUID v4: randomly generated (most commonly used)
- UUID v5: based on SHA-1 hash of a namespace and name
With 2^122 possibilities for UUID v4, the probability of collision is infinitesimal. They are used in databases, APIs, distributed systems, and anywhere a unique identifier is needed.
Number systems in computing
Understanding number bases is fundamental in programming:
Binary (base 2):
- 0 and 1, the native language of computers
- Each position = power of 2
- 1010 binary = 8+0+2+0 = 10 decimal
Octal (base 8):
- Digits 0-7
- Used in Unix permissions (chmod 755)
- Compact for representing groups of 3 bits
Hexadecimal (base 16):
- Digits 0-9 and A-F
- 2 hex characters = 1 byte
- Used for colors (#FF5733), memory addresses, debugging
Quick conversion:
- 4 binary bits = 1 hex digit
- 3 binary bits = 1 octal digit
- 1111 binary = F hex = 15 decimal
Base64: encoding for transport
Base64 converts binary data to ASCII text using 64 characters (A-Z, a-z, 0-9, +, /):
Common uses:
- Email attachments (MIME)
- Data in URLs and JSON
- Embedded images in HTML/CSS (data URIs)
- Authentication tokens
Process:
- 3 bytes (24 bits) → 4 Base64 characters
- Padding (=) completes if data isn't a multiple of 3
Example: "Hello" → "SGVsbG8="
Important: Base64 increases size by about 33%. It's not encryption, just reversible encoding.