Free calculators for real-life decisions
Clear answers for money, work, health, and everyday planning.
Use practical, privacy-friendly calculators built for US users. No sign-up, no confusing spreadsheets—just useful estimates with transparent assumptions.
Featured financial calculators
Salary & Take-Home Pay
Convert pay periods and estimate 2026 federal, payroll, and state taxes.
Income Tax by State
Estimate federal income tax, FICA, state income tax, and take-home income.
Mortgage Calculator
Estimate monthly principal and interest for a home purchase.
Grow and protect your money
Compound Interest
Project investment growth with monthly contributions and flexible compounding.
Retirement Savings
Estimate your future balance, target progress, and illustrative retirement income.
Freelance Rate
Build a sustainable hourly and project rate from income goals and real business costs.
Health, travel, and everyday tools
Calorie & TDEE
Estimate BMR, maintenance calories, and gentle adjustment targets.
Trip Budget
Plan transportation, lodging, food, activities, and a safety buffer.
Currency Converter
Convert common currencies with a current public reference rate.
New privacy-first tools
Work with images and PDFs without uploading them.
These focused tools process selected files inside your browser. No account, no watermark, and no file storage on KokoroFlow.
Image Compressor
Reduce JPG, PNG, or WebP dimensions and file size on your device.
JPG, PNG & WebP Converter
Change common image formats while keeping control of transparency and quality.
DPI & Print Size
Check practical print dimensions or calculate the pixels a print needs.
PDF Merge
Arrange and combine PDF documents locally in the browser.
PDF Split & Reorder
Extract page ranges or create a new custom page order.
EXIF Metadata Remover
Create a clean image copy without common location and camera metadata.
Business Days Calculator
Count weekdays or add workdays using optional custom holidays.
Transparent estimates, built for practical planning
No account required
Most calculations run directly in your browser without collecting personal financial or health details.
Assumptions explained
Financial and health tools show what is included, what is simplified, and where official guidance matters.
Free and mobile-friendly
Use the calculators on a phone, tablet, or computer without a subscription.