All free tools

Browse every utility by category. All tools are free and run privately in your browser.

Developer

DeveloperCron Expression Explainer & Next Run CalculatorDecode any 5-field cron expression and see its next scheduled run times.DeveloperChmod Permission CalculatorConvert Linux file permissions between checkboxes, octal and symbolic notation.DeveloperUmask CalculatorSee the default file and directory permissions that any umask value produces.

Networking

NetworkingCIDR Subnet CalculatorNetwork address, broadcast, mask, wildcard and usable host range for any IPv4 CIDR block.

Design & Accessibility

Design & AccessibilityWCAG Colour Contrast CheckerCheck text and background colour pairs against WCAG 2.1 AA and AAA contrast requirements.

Finance

FinanceLoan Prepayment Savings CalculatorSee how much interest and time you save by paying extra on a home, car or personal loan.

Date & Time

Date & TimeBusiness Days CalculatorCount working days between two dates or add business days to a date, with custom weekends and holidays.Date & TimeMeeting Time Zone PlannerFind the overlap in working hours between up to four time zones for a given date.

Writing & Code

Writing & CodeText Difference CheckerCompare two blocks of text line by line and see exactly what was added or removed.

Writing & SEO

Writing & SEOKeyword Density & Phrase AnalyzerFind the most repeated words and 2-3 word phrases in any text, with counts and density.

Marketing

MarketingUTM Campaign Link BuilderCreate clean, consistent UTM-tagged URLs for Google Analytics campaign tracking.

Design & Media

Design & MediaAspect Ratio & Resolution CalculatorSimplify any width and height to a ratio and scale dimensions without distortion.