Free online tools that just work

Free online calculators, converters and generators. No sign-up, no clutter. Everything runs in your browser.

Popular tools

Reading Time CalculatorWords to minutes for reading aloud, silent reading and speeches, with a conversion table. Loan CalculatorMonthly payment, total interest and payoff date for any loan, with an amortization schedule. Color PickerPick any colour and get HEX, RGB, HSL, CMYK, Lab and OKLCH codes with an eyedropper. YouTube Playlist Length CalculatorAdd up video lengths, see total time at 1.5x and 2x speed and plan your watching.

Guides and how-tos

How to Calculate Mortgage Refinance SavingsWork out monthly savings, break-even and lifetime interest before you refinance. How to Calculate Keto MacrosSet your protein, fat and carbs for your calories and goal, step by step. How to Merge Audio Files OnlineJoin MP3 and WAV files into one track in your browser without uploading. Is Mortgage Refinance Interest Tax Deductible?What you can deduct after a refinance, and what points and cash-out change.

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All categories

Everyday Calculators20 tools: loan, compound interest, percentage, age, BMI, GPA and split-bill calculators. Real Estate Tools19 tools: mortgage refinance, rental yield, BRRRR, house flip and country remortgage calculators. Text & Writing14 tools: word counter, reading time, words to pages, citation generator and fancy text. Social Media Tools26 tools: YouTube, TikTok, Instagram and hashtag generators, plus earnings and engagement calculators. Design & Color Tools10 tools: colour picker, palette generator, gradient generator, colour wheel and HEX to RGB converter. Productivity & Organization Tools10 tools: weekly schedule maker, Pomodoro timer, Gantt chart, Kanban board and habit tracker. Image Tools10 tools: image resizer, compressor, cropper, meme generator, watermark remover and passport photo maker. Recipe & Cooking Tools10 tools: yeast, air fryer and pizza dough calculators, cooking measurement and baking pan converters. Travel Tools18 tools: jet lag, Schengen 90/180, layover, flight time, EU261 and travel budget calculators. Business & Legal Tools6 tools: SBA loan, break-even, startup runway and business valuation calculators, plus an invoice generator. Date, Time & Scheduling Tools6 tools: moon phase, shift schedule, ICS calendar file, time card, working days and time zone planner. Gaming Tools6 tools: dice probability, gacha pity, Elo rating, D&D encounter, loot table and mouse sensitivity. Device Tests3 tools: mouse double click test, scroll wheel test and mouse polling rate test. Typing Tests3 tools: typing speed test, 1 minute typing test and 5 minute typing test. Education & Study Tools8 tools: lesson plan, rubric and syllabus generators, random student picker, group generator and exam timer. Security & Privacy Tools10 tools: IP address, password strength and breach checkers, plus hash, passphrase and encryption tools. SEO & Web Tools10 tools: sitemap validator, schema, meta tag, Open Graph, robots.txt, hreflang and redirect generators. Marketing & Advertising Tools10 tools: QR code, email signature, business name and headline analyzer, plus A/B test and ROI calculators. Email Tools10 tools: email validator, HTML template builder, DMARC and SPF generator, subject line and header tools. PDF & Document Tools11 tools: merge, split, compress, sign and convert PDFs, plus a PDF to text extractor. Audio & Music Tools10 tools: audio merger, cutter, vocal remover, MP4 to MP3 converter, voice recorder and BPM detector. Accessibility Tools10 tools: closed caption generator, text to speech, colour contrast checker, alt text and WCAG tools. Developer Tools5 tools: password, cron expression, README and licence generators, plus a code unminifier. Engineering4 tools: V-belt length, spring rate, stepper motor and bearing L10 life calculators. Construction4 tools: roof pitch, fence post, stair stringer and deck footing calculators. Health & Fitness3 tools: keto macro calculator, sleep cycle calculator and stretching routine generator. Astrology7 tools: zodiac sign, planetary hours, essential dignity, zodiacal releasing and Arabic lots calculators.

About Utiliby

Utiliby is a growing collection of free online tools that run in your browser. Calculators, converters and generators cover everyday maths, money, health, writing, images, PDFs, audio, travel, real estate and more. There is no sign-up, and each tool explains in plain language how it works and where its numbers come from. Read the guides for the formulas behind the tools, or see the about and privacy pages.