Percentage Calculator
X% of Y, share as a percent, and percent change-with formulas, examples, and FAQ in your browser.
OpenMortgage Calculator
Estimate monthly mortgage payments, compare term and rate scenarios, and understand practical trade-offs before applying.
OpenAdvanced APR (RRSO) Calculator
True annual cost of credit (EU RRSO / US APR): fees, commissions, grace periods and balloon payments.
OpenTax Calculator (VAT / GST)
Universal tax calculator. Add or remove VAT, GST or Sales Tax. Automatic rates for all major countries.
OpenSalary Calculator
Gross-to-net salary conversion with full social contributions breakdown - estimate take-home pay in your browser.
OpenCurrency Converter
Live-style FX conversion for 30+ currencies with mid-market context for travel, transfers, and shopping.
OpenInvoice Generator
Free PDF invoice in your browser: line items, VAT per row, discount, shipping, logo, bank notes. pdfmake, no signup.
OpenIncome Tax Calculator
Estimate income tax from gross pay, allowance, and two-rate brackets. Net income and effective rate-runs locally in your browser.
OpenInvestment Calculator
Compound interest and ROI calculator for long-term investment planning.
OpenHosting Comparison
Compare 50+ hosting plans for free. Filter by RAM, storage and price; intro vs renewal from curated research of public sources.
OpenEmployee Cost Calculator
Full employer cost breakdown including social contributions, payroll taxes, and fixed monthly perks.
OpenBMI & WHtR Calculator
BMI and waist-to-height ratio with WHO categories, optional Asian thresholds, metric or imperial.
OpenCalorie Calculator
Mifflin-St Jeor BMR and TDEE with separate NEAT and training activity factors, gender-adjusted protein/fat targets per kg, fiber estimate, and lean-bulk safety tips. Metric or imperial.
OpenUnit Converter
Convert length, mass, volume, temperature, area and speed. Metric and US customary units, instant in your browser.
OpenTip Calculator
Calculate tip, tax, total and per-person split in seconds. Choose pre-tax or post-tax tip base and get instant results in your browser.
OpenQR Code Generator
Generate custom QR codes for URLs, WiFi, vCard, email and text. Add logo, pick colors, choose dot styles. Free, no registration, works in your browser.
OpenAdvanced Password Generator
Generate strong, memorable passwords from your own words. Adjustable strength, crack-time estimates, 100% in your browser.
OpenDiscount & Sale Price Calculator
Calculate sale price after a discount, find the discount percentage, or reverse-engineer the original price. Free, instant, in your browser.
OpenAge & Date Calculator
Calculate exact age, the difference between two dates, or add and subtract days, weeks, months, and years. Free, instant, in your browser.
OpenHash Generator
Compute MD5, SHA-1, SHA-256, SHA-384, and SHA-512 from text or files.
OpenTime Zone Converter
Convert time across world time zones with DST-aware offsets. Compare UTC, Europe, America, Asia, and Pacific zones in one view.
OpenUUID / GUID Generator
Generate UUID v4, v1, and v7 online. Batch up to 100, copy or download as TXT.
OpenBinary / Hex / Dec / Oct Converter
Convert numbers between decimal, binary, hexadecimal, and octal. Signed mode, digit grouping, instant sync.
OpenPrice Markup & Margin Calculator
Calculate markup, margin, and sale price. See the difference between markup on cost and margin on price.
OpenSales Commission Calculator
Calculate sales commission: flat rate, tiered brackets, or team split. Free, instant, in your browser.
OpenMeeting Cost Calculator
See how much a meeting really costs: participants, duration, hourly rates, and a live cost clock. Free in your browser.
OpenRunning Pace & Race Time Calculator
Calculate running pace, finish time, or distance. Preset race distances, split table, km/mi toggle. Free in your browser.
OpenLoan Calculator
Calculate EMI, compare up to three loan offers, check affordability from income, analyze refinance costs, and model prepayment with Smart Summary, charts, and amortization table.
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