Calculator Tools
7 free calculator tools that run entirely in your browser.
Chmod Calculator
Calculate Unix file permissions in octal and symbolic notation.
IP Subnet Calculator
Calculate network address, broadcast, host range, and subnet mask from CIDR notation.
Cron Next Run Times
Enter a cron expression and see the next scheduled run times in your timezone.
Aspect Ratio Calculator
Calculate aspect ratios and scale dimensions while keeping proportions.
PX to REM Converter
Convert between px and rem/em based on a root font size.
Data Size Converter
Convert between bytes, KB, MB, GB, and binary KiB/MiB units.
Semver Calculator
Bump and compare semantic versions (major/minor/patch).
About calculator tools
These 7 calculator tools cover the tasks developers reach for most. Each one runs client-side, so your input never leaves your device and every tool works offline after the first visit. No account, no upload, no tracking.