Free Toolbox
The Toolbox
Free calculators and utilities for business owners, founders, and operators. No sign-up. No nonsense.
Financial & Pricing
Gross Margin Calculator
Calculate gross margin percentage and gross profit from revenue and cost of goods sold.
Markup vs Margin Calculator
Understand the difference between markup and margin, and convert between the two instantly.
Break-Even Calculator
Find how many units you need to sell — and at what revenue — to cover your fixed and variable costs.
VAT Calculator
Add or remove VAT from any amount. Supports any VAT rate including UK (20%), EU, and custom rates.
Invoice Calculator
Build up an invoice with multiple line items, apply discounts and VAT, and get your total instantly.
SaaS Pricing Calculator
Model your SaaS pricing tiers and see monthly and annual revenue across customer segments.
MRR & ARR Calculator
Calculate Monthly Recurring Revenue and Annual Recurring Revenue from your subscription customer base.
Burn Rate & Runway Calculator
Calculate your monthly cash burn rate and how many months of runway you have left.
Customer LTV Calculator
Calculate Customer Lifetime Value from average revenue per user, churn rate, and gross margin.
CAC Calculator
Calculate Customer Acquisition Cost and your LTV:CAC ratio — the key metric for sustainable growth.
ROI Calculator
Calculate Return on Investment, annualised ROI, and net profit from any investment or project.
Payback Period Calculator
Calculate how long it takes to recover an investment from monthly cash flows or annual returns.
DDP Import Cost Calculator
Calculate total landed cost for imports under Delivered Duty Paid terms — including duty, VAT, and shipping.
Percentage Calculator
Calculate percentages instantly — find X% of Y, what percentage X is of Y, and percentage change between two values.
Compound Interest Calculator
Calculate how your money grows with compound interest over time. See year-by-year breakdown and future value.
Loan & Mortgage Calculator
Calculate monthly repayments, total interest, and total cost for any loan or mortgage.
Automation & Tech
Cron Expression Builder
Build cron expressions visually and get a plain-English description of when your job will run.
JSON Formatter & Validator
Paste any JSON to format, minify, and validate it instantly — with clear error messages.
Unix Timestamp Converter
Convert between Unix timestamps and human-readable dates and times, in UTC and local time.
UUID Generator
Generate cryptographically random UUID v4 values — one at a time or in bulk.
Base64 Encoder / Decoder
Encode plain text to Base64 or decode Base64 back to plain text — instantly in your browser.
URL Encoder / Decoder
Percent-encode URLs for safe transmission, or decode encoded URLs back to readable text.
Regex Tester
Test regular expressions against sample text with live match highlighting and group capture display.
QR Code Generator
Generate QR codes instantly for any URL, text, or data. Download as PNG — no sign-up required.
Hash Generator
Generate SHA-256, SHA-1, and SHA-512 hashes from any text — entirely in your browser.
Text Case Converter
Convert text between camelCase, snake_case, PascalCase, kebab-case, SCREAMING_SNAKE, Title Case, and more.
Colour Picker & Converter
Pick a colour and convert between HEX, RGB, and HSL formats instantly.
Image to Base64 Converter
Convert any image file to a Base64 data URI for embedding directly in HTML, CSS, or JSON.
Business Operations
UTM Link Builder
Build UTM-tagged URLs for campaign tracking in Google Analytics and other analytics platforms.
Reading Time Estimator
Paste any text to instantly see word count, estimated reading time, and speaking time.
SEO Meta Tag Checker
Check your page title and meta description length against Google's limits with a live search preview.
Password Generator
Generate strong, random passwords with custom length and character set options.
URL Slug Generator
Convert any title or phrase into a clean, SEO-friendly URL slug.
Word Frequency Counter
Paste any text to see the most-used words ranked by frequency. Useful for content analysis and SEO.
Aspect Ratio Calculator
Calculate aspect ratios, scale image dimensions proportionally, and find missing width or height values.
Age & Date Calculator
Calculate exact age from a date of birth, and find the difference between any two dates in years, months, and days.