Small tools I use often

Everyday

• Percentage Calculator Percent of a number, percent change, and more.
• Aspect Ratio Calculator Scale a width and height while keeping the same ratio.
• QR Code Generator Links, text, WiFi and contacts. Download as PNG or SVG.

Money

• Employee Cost Calculator (Mexico) Total cost to the company, net pay, IMSS, ISR and a benefits calendar.
• IVA Calculator Add or remove Mexican IVA (16% or 8%).
• Compound Interest Calculator Growth over time with regular contributions.

Developer & design

• JSON Formatter Format, minify and validate JSON.
• Base64 Encoder / Decoder Encode and decode text or files.
• Color Contrast Checker Check text and background colors against WCAG.