Investing & Finance Calculators
InvestingDCA Calculator (Dollar-Cost Averaging)
Project a regular-investment plan with weekly or monthly contributions
Dividend Reinvestment (DRIP) Calculator
Model a dividend portfolio with growing payouts and reinvested dividends
Stock Profit Calculator
Net gain, ROI and break-even price after buy/sell commissions
Position Size Calculator (Risk Management)
Share count and position size from your stop-loss and per-trade risk
CAGR Calculator (Compound Annual Growth Rate)
Annualized growth between two values, with total return and Rule of 72
PE & PEG Ratio Calculator
Price-to-earnings, earnings yield and PEG from price, EPS and growth
Investment Fee Calculator (Expense Ratio)
See how an annual fund fee compounds into a large long-term cost
Hong Kong Stock Trading Fee Calculator
Stamp duty, SFC/AFRC levies, HKEX fee, CCASS and broker commission for HK stocks
Text & Developer Tools
Text & DeveloperWord Counter
Count characters, words, sentences, paragraphs & reading time as you type
JSON Formatter & Validator
Beautify, minify and validate JSON with clear error messages
Base64 Encode & Decode
Convert text to/from Base64 with correct UTF-8 and emoji support
URL Encode & Decode
Percent-encode/decode URLs and query parameters, RFC 3986 safe
Case Converter & Text Cleaner
UPPER, lower, Title, camelCase, kebab/snake, trim, dedupe & sort lines
Color Converter HEX / RGB / HSL
Convert between HEX, RGB and HSL with a picker and live preview
Unix Timestamp Converter
Convert epoch timestamps to dates and back, auto-detects seconds/ms
Base Converter (Binary/Octal/Decimal/Hex)
Convert numbers across binary, octal, decimal and hexadecimal instantly
Regex Tester
Live match highlighting and a match list with g/i/m flags
Text Diff Checker
Compare two texts line by line with added/removed lines highlighted
CSV ↔ JSON Converter
Turn spreadsheets into JSON arrays and back, handles quoted commas
UUID / GUID Generator
Generate RFC-4122 v4 UUIDs in bulk, with uppercase or no-dash options
Hash Generator (SHA-1/256/384/512)
Compute SHA digest fingerprints of text, fully in your browser
Image to Base64 (Data URL)
Convert an image to a Data URL for HTML/CSS embedding, all locally
Calculators & Converters
CalculatorsLife, Health & Money
Life & MoneyBMI Calculator
Calculate BMI with metric or imperial units and WHO weight categories
Loan & Mortgage Calculator
Monthly payment, total interest and amortization schedule for a fixed loan
Age Calculator
Exact age, days alive, next birthday and Western & Chinese zodiac signs
BMR & TDEE Calculator
Basal metabolic rate and daily calorie needs via Mifflin-St Jeor
Compound Interest Calculator
Future value with an initial lump sum plus monthly contributions
Discount & Sale Calculator
Enter original price and percent off to get the sale price and savings
Fuel Calculator (MPG & L/100km)
Work out MPG, L/100km and cost per mile or kilometre
Number to Words Converter
Spell numbers in English, with check-writing format (dollars and cents)
Generators & Utilities
GeneratorsPassword Generator
Strong random passwords with custom length and charset, made offline
Date Calculator
Days between two dates, or add/subtract days, weeks or months
Image Compressor
Shrink JPG/PNG/WebP locally with adjustable quality and size — no upload
Image Converter (JPG/PNG/WebP)
Convert and resize between JPG, PNG and WebP locally — no upload
Stopwatch & Countdown Timer
Online stopwatch with laps and a countdown timer — works in the tab
Random Number Generator & Name Picker
Generate random integers in a range or draw names from a list
Online Notepad
Type and auto-save in your browser, copy or download as TXT, private
About No1 Tools
No1 Tools (tools-no1.com) is a growing collection of free online tools that turn the small, repetitive tasks of work, study and daily life into one-click web apps: count words while writing, format JSON and encode Base64 while developing, plan a loan or compound-interest goal, check your BMI, and compress an image before sending it. There is no software to install and no account to create.
Why browser-based tools
Compared with downloadable software, web tools are cross-platform, take no storage and update instantly. Wherever possible we run the calculations locally in your browser, so text and images never touch a server — reassuring when you handle contracts, ID photos or API data. Every page is mobile-friendly, so you can get things done on your phone as easily as on a desktop.
Who it is for
Students and writers, developers and IT professionals, people who work with spreadsheets and money, households planning loans or health metrics, and creators or online sellers who constantly resize and convert images. Press Ctrl+D (or bookmark on mobile) to keep us within reach.
Frequently asked questions
Do I need to download or install anything?
No. Every tool is a free web app that runs in the browser on your phone, tablet or computer. Just open tools-no1.com/en — there is nothing to install and no account required.
Are my inputs and files uploaded to a server?
Most tools run entirely in your browser and process your text, numbers and images locally. For example the word counter and image compressor never upload your content, which is safer for private data.
Are the tools free?
Yes, all tools are free to use and the core features will stay free. You can bookmark the site for quick access any time.
Does it work on mobile?
Yes. The whole site is responsive and works smoothly in Safari, Chrome and other browsers on phones and tablets as well as desktops.
Will more tools be added?
Yes, new high-frequency tools that can run safely and locally are added regularly. Suggestions are welcome through the Contact page.