Free online tools

Base64 Decode / EncodeEncode text or files to Base64 and decode Base64 strings back to their original form. Useful for embedding data in URLs, JSON, data URIs and config files — all processed in your browser.base64decode.tools URL Encode / DecodePercent-encode URLs and query components, or decode encoded strings back to readable text. Handles reserved characters, spaces and unicode so your links and parameters stay valid.urlencodedecode.com UUID GeneratorGenerate universally unique identifiers in bulk, across multiple versions, for database keys, API tokens and distributed systems. Copy one or thousands at a time.uuidcore.com JSON ToolsFormat, validate, repair and explore JSON with a tree view and clear error reporting. Fix broken JSON with 20+ repair rules and read deeply nested data without the headache.jsontools.tools Hash GeneratorCompute MD5, SHA-1, SHA-256 and 30+ other hashes from text or files using a pure-JavaScript engine. Includes plain-language notes on which algorithms are safe to use today.hashgenerator.tools Epoch / Unix Time ConverterConvert Unix timestamps to human-readable dates and back, in seconds or milliseconds, across time zones. A quick reference for logs, APIs and database timestamps.epochtime.tools Crontab Cheat SheetBuild cron schedule expressions visually and decode existing ones into plain English. See exactly when a job will run before you commit it to your server.crontabsheet.com Regex GuideLearn, build and test regular expressions with live matching and clear explanations of each token. A practical reference for both beginners and experienced developers.regexguide.com Password Strength CheckerTest how strong a password really is against common cracking patterns, with feedback on length, entropy and reuse. Checked entirely in your browser — nothing is sent anywhere.passwordstrength.net CIDR CalculatorPlan IP address ranges and subnets from CIDR notation — network, broadcast, usable hosts and mask. Built for network engineers and anyone designing an address scheme.cidrcalculator.net Subnet Mask CalculatorFull IPv4 and IPv6 subnetting with VLSM planning, cloud-native modes and infrastructure-as-code export. A complete toolkit for designing and documenting networks.subnetmaskcalc.net Internet Speed TestTest your download, upload and ping speed straight from the browser, with a clear readout of latency and throughput. A quick way to check whether your connection is performing as it should.checkinternetspeed.tools What Is My IPSee your public IP address along with the location, ISP and browser details that websites can detect. Useful for troubleshooting connections, VPNs and network setups.checkmyipnow.com WHOIS LookupLook up domain registration, ownership, expiry dates and DNS records for any website. Handy for buying domains, checking renewals and researching who runs a site.whoislookuppro.com

Word CounterCount words, characters, sentences and paragraphs in real time, with estimated reading and speaking time. Handy for essays, articles, social posts and meeting scripts.wordcounterfree.com Case ConverterConvert text between UPPERCASE, lowercase, Title Case, Sentence case, camelCase and more in one click. Clean up pasted text or reformat headings and code instantly.transformcase.com Text RepeaterRepeat any word, phrase or line a chosen number of times, with optional separators and new lines. Useful for testing, placeholder content and bulk formatting.textrepeat.net Number to WordsConvert numbers into written words for cheques, invoices, contracts and legal documents. Handles currency and large figures so amounts read exactly as they should.numtotext.com

Square Footage CalculatorCalculate area in square feet or metres for rooms, floors, walls and land — including irregular shapes. Ideal for flooring, painting, tiling and real-estate estimates.thesquarefootagecalculator.com Percentage CalculatorWork out percentages, percentage increase and decrease, and the difference between two numbers. Covers discounts, tips, tax, grades and everyday "what percent of" questions.bestpercentagecalculator.net Age CalculatorFind an exact age in years, months, weeks and days between any two dates, plus upcoming birthdays and milestones. Useful for forms, eligibility checks and planning.theagecalculator.net Hours CalculatorAdd up hours and minutes between start and end times, with breaks, to total a timesheet or work shift. Convert between decimal hours and hours-and-minutes easily.calculatehours.net Box Volume CalculatorCalculate the volume and capacity of boxes and containers from length, width and height, in metric or imperial units. Handy for packing, shipping and storage planning.boxvolumecalculator.com Dimensional Weight CalculatorWork out shipping dimensional (volumetric) weight across 17 carriers so you can predict postage costs before you ship. Compare actual versus billable weight at a glance.dimweightcalc.com Girth CalculatorCalculate package girth for carrier size limits, plus body-measurement girth for fitness tracking. Two related measurements in one clean, private tool.girthcalculator.com Margin vs Markup CalculatorConvert between profit margin and markup, and see how each affects your selling price. Clears up one of the most common pricing mistakes in retail and wholesale.marginvsmarkup.com EMI CalculatorCalculate loan EMIs, total interest and a full amortization schedule for home, car and personal loans. See exactly how much each payment goes to principal and interest.indiaemi.com Solar CalculatorEstimate the solar system size, panel count and potential savings for your energy use and roof. A practical starting point before talking to an installer.prosolarcalc.com Unit Cheat SheetA quick reference for converting between common units of length, weight, volume, area and temperature. Find the conversion you need without digging through menus.unitcheatsheet.com Total Interest CalculatorSee the total interest paid over the full life of a loan across different terms and rates. Compare scenarios before you commit to a repayment plan.totalinterestcalc.com SIP CalculatorProject the returns of a mutual fund SIP using your expected rate, tenure and optional step-up contributions. Plan long-term investing goals with realistic numbers.sipcalculatorhub.com Calorie CalculatorEstimate your daily calorie needs, BMR and macro split for weight loss, maintenance or gain. A simple starting point for planning meals and tracking intake.calorieskit.com BMI & BMR CalculatorCalculate body mass index and basal metabolic rate from your height, weight, age and sex. Understand where you stand and how many calories your body burns at rest.bmibmrcalc.com Fraction CalculatorAdd, subtract, multiply and divide fractions with clear step-by-step working shown for each result. Great for homework, recipes and everyday fraction math.fractionsteps.com GPA CalculatorCalculate GPA and cumulative CGPA from your grades and credit hours on a range of scales. Track academic progress and work out what you need next term.gpacalculatorhq.com Voltage Drop CalculatorCalculate voltage drop across a wire run from gauge, length, current and conductor material. Size cables correctly and keep circuits within safe limits.voltdropcalc.com AC Tonnage CalculatorEstimate the air-conditioner size in tons needed for a room based on area, climate and insulation. Avoid buying a unit that is too small or wastefully large.actonnagecalc.com Backup Power CalculatorSize a generator or battery backup from the total wattage of your appliances and the runtime you need. Plan for outages without over- or under-spending.backuppowercalc.com Solar Battery Bank CalculatorSize a solar battery bank from your daily load, days of autonomy and depth of discharge. Design an off-grid or backup storage system with confidence.solarbatterybankcalc.com Tank Volume CalculatorCalculate the volume and fill level of cylindrical, rectangular and oval tanks in any unit. Useful for water storage, fuel, aquariums and industrial vessels.tankvolumecalc.com Pool Volume CalculatorWork out the water volume of a swimming pool in gallons or litres for any shape and depth. Get the numbers you need for chemicals, heating and refills.poolvolumecalc.com Cubic Yardage CalculatorCalculate cubic yards of concrete, gravel, mulch, soil or sand for a project from simple dimensions. Order the right amount of material without guesswork.cubicyardage.com Concrete Material CalculatorEstimate the concrete, cement, sand and aggregate needed for slabs, footings and columns. Plan a pour and buy materials in the correct proportions.concretematerialcalc.com Roofing Material CalculatorEstimate shingles, underlayment and other materials from your roof area and pitch. Budget a re-roof and reduce leftover waste before you order.roofingmaterialcalc.com Stair CalculatorWork out stair rise, run, stringer length and the number of steps to meet building code. Plan a safe, comfortable staircase before cutting any timber.staircalculators.net Construction CalculatorsA hub of construction calculators for materials, areas, volumes and project estimates in one place. Handy for builders, contractors and DIY projects.constructioncalchq.com Cooking Measurement ConverterConvert cups, grams, ounces, millilitres and spoons for any recipe with reliable kitchen measurements. Scale servings up or down without the guesswork.measurechef.com

Clock With UsLive clocks and a clean time-zone reference for checking the current time in cities around the world. Useful for scheduling calls and coordinating across regions.clockwithus.com

Image ToolkitCompress, convert, resize and crop images privately in your browser, with optional advanced compression. Your photos never leave your device — nothing is uploaded.pictoolkit.com PDF ToolsMerge, split, reorder and manage PDF files entirely in the browser. Combine documents or pull out pages without uploading sensitive files to a server.corepdftools.com Remove MetadataStrip EXIF, location and other hidden metadata from photos and files before you share them. A simple privacy step that runs locally and reveals what was hidden.removemetadata.tools Color Code KitA developer color toolkit for converting between HEX, RGB, HSL and OKLCH, building palettes and generating design tokens. Everything a designer or front-end dev needs in one place.colorcodekit.com