One question. One page.
The answer is free.
27 single-purpose browser tools for the jobs that come up once or twice a year and are weirdly hard to trust elsewhere: how many days you have left in the Schengen area, what an overpayment actually saves, how much gravel a driveway needs, or how to redact a PDF without uploading it to someone else's server.
27 toolsFree answersFormulas shownNo account
All 27 tools
Every page answers its main question for free, and opens with the complaints it was built to fix. Pro, where offered, adds the paperwork that follows the answer — a report, a batch run, a saved scenario.
Schengen 90/180 Rolling Stay Calculator
Plan past and future European trips with exact 180-day rolling window validation and earliest re-entry dates.
CalculatorMortgage Overpayment & Payoff Calculator
See exactly how much interest and how many years you shave off your UK/AU/US mortgage with recurring or lump-sum overpayments.
ConverterLocal Browser Batch HEIC to JPG Converter
Convert hundreds of iPhone HEIC photos to JPG or PNG 100% locally in your browser without uploading a single byte.
File stays in this tabCalculatorUK/AU Stamp Duty Property Tax Calculator
Calculate exact UK SDLT, Scottish LBTT, or Australian state transfer duty across first-time buyer, mover, and buy-to-let tiers.
ConverterSewing PDF Pattern Stitcher & Projector Tool
Stitch multi-page A4/Letter sewing PDFs into a single calibrated large-format sheet or interactive projector view.
File stays in this tabCalculatorCoast FIRE & Retirement Pension Calculator
Find the exact portfolio balance where you can stop saving for retirement and let compound growth fund your target lifestyle.
ConverterClient-Side PDF Redaction & Sanitizer Tool
Permanently burn black redaction boxes into sensitive PDFs and strip hidden text layers locally in your browser.
File stays in this tabCalculatorBaker's Percentage & Pizza Dough Calculator
Scale sourdough, Neapolitan, or NY-style pizza dough by ball count, weight, hydration, and starter inoculation.
GeneratorBrowser Booklet Imposition Layout Tool
Convert any standard sequential PDF into saddle-stitch or multi-signature print-ready booklet sheets in seconds.
File stays in this tabTrackerTax Residency & FEIE 330-Day Tracker
Track cross-border travel logs against the US FEIE 330-day rule, US Substantial Presence Test, and 183-day tax residency thresholds.
ConverterBaking Pan Size & Recipe Scaling Converter
Convert any cake or baking recipe between round, square, rectangular, and springform pans while scaling every ingredient.
CalculatorTravel Nurse GSA Per Diem Pay Calculator
Compare travel nurse contract packages by breaking down taxable hourly wages, tax-free GSA stipends, overtime, and true net pay.
CalculatorIVF FET Due Date & Milestone Calculator
Calculate accurate IVF due dates for Day 3, Day 5, or Day 6 embryo transfers along with beta hCG and ultrasound milestones.
CalculatorMini-Split Heat Pump BTU Sizing Calculator
Size single-zone or multi-zone ductless mini-split heat pumps accurately by room volume, insulation, sun exposure, and climate zone.
PlannerGallery Wall & Photo Frame Layout Planner
Arrange picture frames on a scaled wall canvas and get exact nail-hole measurements from the floor and wall edge.
ConverterKnitting Gauge Swatch & Stitch Converter
Recalculate any knitting or crochet pattern stitch and row counts when your gauge swatch doesn't match the pattern.
CalculatorAustralia Visa 8558 Stay Calculator
Ensure your parents or visitors never breach Australia Visa Condition 8558 (max 12 months stay in any 18-month rolling period).
CalculatorGerman Tax Class & Elterngeld Optimizer
Find the optimal Steuerklasse (3/5 vs 4/4) switch deadline to maximize both monthly net pay and German Elterngeld parental benefit.
CalculatorAustralia MLS vs Private Health Calculator
Calculate your exact Australian Medicare Levy Surcharge (MLS) and see whether buying basic hospital cover saves you money at tax time.
CalculatorGravel Driveway Volume & Tonnage Calculator
Calculate exact cubic yards, tons, dump-truck loads, and multi-layer base/topcoat costs for any gravel driveway or path.
CalculatorNo Tax on Tips & Overtime Calculator (OBBBA)
Estimate your 2025-2026 no-tax-on-tips and no-tax-on-overtime deductions (Schedule 1-A) with exact caps, premium-half math and MAGI phaseouts.
ConverterBank Statement PDF to CSV Converter
Convert text-layer bank statement PDFs into clean CSV for spreadsheets and accounting apps — 100% in your browser, statements never uploaded.
File stays in this tabConverterDark Slide Ink-Saver Inverter
Print dark lecture slides as ink-friendly light pages — backgrounds invert, photos stay true, toner coverage drops by half or more.
File stays in this tabCalculatorState PFML Benefit Calculator (13 States + DC)
Estimate your 2026 paid family & medical leave weekly benefit for every state program — tiered formulas and caps for all 13 states plus DC built in.
CalculatorBYOB Wedding Alcohol & Ice Calculator
How much beer, wine, liquor and ice to buy for your wedding — vendor-standard consumption math with case quantities, return buffer and cost per guest.
CalculatorRiver Table Epoxy Volume & Pigment Calculator
Exact resin, hardener and pigment amounts for river tables — multi-point width averaging, seal coats, mixing loss and deep-pour layer limits included.
CalculatorStair Stringer & Railing Calculator with SVG Cutting Diagram
Riser, run, stringer throat and railing counts that pass IRC code — with a to-scale cutting diagram and the finished-floor fix for trippy first steps.
Why these tools work differently
Three things you can check yourself, on the page, in under a minute.
The math is on the page
Tools print the formula — or the rule — and the intermediate numbers they used. If a result looks off, you can see where it went wrong and tell us.
Files never leave the tab
The file tools decode in browser memory — nothing is uploaded, and those pages carry no ad slot. Open the Network tab and watch a file go nowhere.
No account, no sign-up, anywhere
No email gate before a result, no account wall, no subscription. Static pages with no database — which is also why there is nothing to log into, and nothing to leak.
How this site is paid for
Three things, all of them visible on the page rather than hidden in a funnel.
Every core answer stays free
No result is ever behind a paywall — 8 tools have no Pro tier at all. Where Pro exists, it buys exports, batch runs and saved scenarios, never the answer.
One-time unlocks, not renewals
Each Pro unlock is a single payment, priced on the tool's page. No subscription anywhere — an annual fee for a tool you use twice a year is a bad trade.
One labelled ad slot, where it belongs
On non-file pages, one marked ad slot sits below the tool and its result and never interrupts an input. The file tools carry no ad slot at all — a banner next to your bank statement is the wrong trade.
See what Pro adds, tool by tool →
Something looks off? Tell me which tool and what you entered — wrong numbers in a tax or visa calculator are the one thing this site cannot afford.