Free Online Tools and Calculators, No Sign-Up

The money tools, and the reason most people find this site. Several are country-specific because tax is country-specific, and a generic salary calculator that ignores which country you live in is worse than no calculator at all.

• Free Invoice Generator — invoices, quotes and receipts as a PDF, or as an XRechnung, Factur-X or UBL e-invoice, with EU VAT worked out
• VAT Calculator — add or remove VAT at any rate, with standard-rate presets for 30+ countries
• German Salary & Tax Calculator — gross to net, with tax class, church tax and social contributions
• UK Take-Home Pay Calculator — income tax, National Insurance and student loan plans
• Loan & Mortgage Calculator — monthly payment, total interest and a full amortisation schedule
• Compound Interest Calculator — what regular contributions actually grow into, and over what timescale
• Debt Payoff Calculator — snowball against avalanche, so you can see what each strategy really costs
• Inflation Calculator — what a sum from one year is worth in another
• Crypto Profit & DCA Calculator — profit, loss and the average entry price of a dollar-cost-averaging plan
• Freelancer Hourly & Day Rate Calculator — the rate you need once holidays, sick days and downtime are counted
• Hours & Time Card Calculator — add up shifts, subtract breaks, get billable totals
• Card Foreign Transaction Fee Calculator — what a card charges you on top of the exchange rate
• IBAN Validator — checksum-verify an IBAN before you send money to it
• Discount & Percent-Off Calculator — the real price after one discount or several stacked
• Tip Calculator — split a bill and a tip across any number of people

The newest group, and the one that works differently from every other free PDF site. Your file is never uploaded, because there is no server to upload it to — the browser opens the PDF, edits it, and hands it back. That is also why there are no daily task limits, no file-size tiers, no accounts and no watermarks on the output.

It matters most for the documents you would hesitate to hand to a stranger: signed contracts, payslips, medical letters, ID scans. Those never leave your machine here. Start at the PDF tools hub to use every one of them on a single page, or open any one on its own.

• Merge PDF — combine any number of files into one, dragging to set the order
• Edit PDF — fill forms, sign, annotate, cover and draw, then flatten to a normal PDF
• Compress PDF — shrink a scan or photo-heavy file dramatically; text stays sharp and selectable
• Split PDF — extract a page range, cut a file into equal chunks, or save every page separately
• Delete & Organize PDF Pages — every page as a thumbnail: delete, rotate, and drag to reorder
• Rotate PDF — turn sideways pages the right way up and save the rotation permanently
• Sign PDF — draw or type a signature and place it on the page at full size, then flatten it in
• Watermark PDF — stamp text or your logo across every page, in nine placements
• Add Page Numbers to PDF — six positions, five formats, your typeface and colour, cover page skippable
• JPG to PDF — photos, scans and screenshots into one document, cropped if they need it, one per page or arranged freely
• PDF to JPG — pages as JPG, PNG or WebP at anything from 72 to 600 DPI
• PDF to Text — every word as a plain .txt file, scanned pages read with OCR on your device

Standard clinical and sports-science formulas, with the formula named on each page so you can check it against your own source. None of these replaces a doctor or a midwife, and each page says so where it matters.

• BMI Calculator — body mass index in metric or imperial, with the category ranges
• BMR Calculator — resting metabolic rate by the Mifflin-St Jeor equation
• Calorie Calculator — daily intake for maintaining, losing or gaining weight
• Body Fat Calculator — the US Navy circumference method
• Ideal Weight Calculator — four published formulas side by side, because they disagree
• Pace Calculator — pace, time and distance for running and cycling
• Due Date Calculator — estimated delivery date from a last period or conception date
• Pregnancy Calculator — current week, trimester and remaining time
• Pregnancy Conception Calculator — the likely conception window from a known due date

The tools we built because we needed them ourselves while running this site. Generators here produce text you paste into a real config file, so each one shows you the output before you commit it anywhere.

• SERP Snippet Preview — how a title and description will really truncate in Google
• Open Graph & Twitter Card Meta Tag Generator — the social preview tags, ready to paste
• Robots.txt Generator — allow and disallow rules without the syntax traps
• .htaccess & Nginx Redirect Generator — the same redirect written for either server
• Reading Time & Word Count Calculator — word count and an honest reading estimate
• Hosting Bandwidth Calculator — the traffic a plan actually supports
• Website Downtime Cost Calculator — what an outage costs in revenue
• Regex Tester & Explainer — test a pattern and get it explained in words
• Cron Expression Builder — build a cron line and read back when it will fire
• IP Subnet Calculator — network, broadcast, usable range and host count from CIDR

Format shifting, mostly. These are the ones where sending the file somewhere would be the worst part of the job — a customer list, an export, a spreadsheet with real names in it. Everything is converted in the page.

• CSV to JSON Converter — with header detection and nested-key options
• CSV Cleaner — remove duplicate rows and split a combined column
• Markdown to HTML Converter — Markdown in, clean HTML out
• Base64 & URL Encoder / Decoder — both directions, both encodings
• Text Case Converter — sentence, title, camel, snake, kebab and the rest
• PNG & JPEG to WebP Converter — smaller images without an upload round trip
• Random Number Generator — a range, a count, and optional no-repeats

The largest group. Some are quick arithmetic you could do on paper; the value there is speed and not making a slip. Others — the solvers, the grade converters — do a job that is genuinely tedious by hand.

• Percentage Calculator — every phrasing of the question, in one place
• Scientific Calculator — full function set, keyboard-driven
• Unit Converter — length, mass, volume, temperature, area, speed and data
• Fraction Calculator — arithmetic on fractions, simplified as it goes
• Statistics Calculator — mean, median, mode, standard deviation and quartiles
• Geometry Calculator — area, perimeter and volume for the standard shapes
• Triangle Solver — solve any triangle from three known values
• Linear Equation Solver — single equations and systems, with the steps
• Quadratic Equation Solver — roots, discriminant and vertex
• Exponent & Root Calculator — powers and roots of any index
• GCF & LCM Calculator — greatest common factor and lowest common multiple
• Prime Number Checker — primality plus the factors when it is not prime
• Ratio & Proportion Calculator — scale a ratio or solve for the missing term
• Number Base Converter — binary, octal, decimal, hex and anything between
• Roman Numeral Converter — both directions
• Multiplication Table Generator — printable tables at any size
• Age Calculator — exact age in years, months and days
• Date Calculator — the gap between dates, or a date a given interval away
• GPA Calculator — weighted and unweighted, per semester or cumulative
• Grade Calculator — your current grade and what the final needs to be
• ECTS Converter — credits between European systems
• German Grade Calculator — a foreign grade on the German 1.0–4.0 scale by the Modified Bavarian Formula

Optics maths for people who would rather work it out before the shoot than after. Each takes a real sensor size rather than assuming full frame.

• Depth of Field Calculator — near and far limits for a given aperture and distance
• Hyperfocal Distance Calculator — where to focus for maximum sharpness front to back
• Crop Factor & Equivalent Focal Length Calculator — what a lens really gives you on your sensor
• Print Size & DPI Calculator — how big a file can print before it falls apart
• Photo & Video Storage Calculator — card and drive space for a given shoot
• Aspect Ratio Calculator — resize while keeping the proportions

Two specialists that do not belong to any of the groups above.

• Color Converter & Palette — HEX, RGB, HSL and a generated palette from any starting colour
• Strong Password Generator — generated in your browser with the operating system’s cryptographic randomness, so the password is never transmitted anywhere

Every one of these free online tools is a JavaScript program that your browser downloads once and then runs on your own device. There is no calculation server, no queue, and no database with your inputs in it. That is not a policy we promise to keep — it is a description of how the code is built, and you can verify it rather than take our word for it. The PDF tools, for example, run on the open-source pdf-lib engine — code anyone can read.

Open your browser’s developer tools, switch to the Network tab, and use any tool here. Nothing is transmitted while it works. Or load a page, put the device into airplane mode, and keep using it. A tool that sent your data away could not do either.

The practical consequences are the ones people notice: no account, no email address, no daily limits, no file-size tiers, and no upgrade prompt at the point you need the thing to work. The tools also stay usable on a phone, since the work happens locally rather than depending on a connection holding up.

The site pays for itself through affiliate links in our hosting and tech reviews, not through the tools. That is why the tools can stay free without a catch attached to them.

Are these tools really free?

Yes — these are completely free online tools, every one of them, with no paid tier and nothing held back. There is no account to create and no trial to expire.

Do you store what I type into a calculator?

No. The calculation runs in your browser and the numbers never leave it, so there is nothing on our side to store. The one thing recorded is an anonymous count of how often each tool page is opened, which is what drives the “Frequently used” strip at the top of this page. It counts page views, not inputs.

Do the PDF tools upload my documents?

No. The PDF engines run as JavaScript in the page, so your file is opened, edited and saved on your own machine. That is why there are no task limits and no watermarks, and why a signed contract or a payslip is safe to work on here.

Do they work on a phone?

Yes. Every tool is built to work at phone width, and because the work is done on the device rather than on a server, a weak connection does not slow the tool down once the page has loaded.

Can I put one of these tools on my own site?

Several of them, yes. Tool pages that support it have an embed box with a snippet you can copy into your own page, and the embedded tool works the same way — in your visitor’s browser, with nothing sent to us.

How do I find the tool I need?

Use the search box at the top of this page. It matches the tool name, its description and its category as you type, so searching for “tax”, “convert” or “pdf” narrows the whole catalogue of free online tools down immediately. The category buttons next to it filter the same list.