About Boltly

We build simple tools that do one thing well: work out a loan payment, count the words in an essay, shrink a photo, make a QR code or generate a strong password. Each tool has its own page, with short instructions, an explanation of how the result is worked out and answers to common questions, so you can see what a tool is doing and decide whether to trust it.

Every tool runs in your web browser. The numbers you type, the text you paste and the images you choose are processed on your own device and are not uploaded to our servers. We have no sign-up and we do not ask for personal details to use a tool. You can read more in our Privacy Policy.

• Finance Calculators: 10 tools. Loans, mortgages, savings, tax and everyday money maths.
• Everyday Calculators: 6 tools. Percentages, dates, BMI, unit and time zone conversions.
• Text and Formatting: 6 tools. Count, convert, compare and clean up your text.
• Image Tools: 4 tools. Compress, resize and convert images without uploading them.
• Generators: 4 tools. QR codes, passwords, barcodes and random numbers.

Calculators use standard, published formulas, and each one is checked with automated tests against known reference values and edge cases such as zero interest or empty input. Even so, results are estimates for general information. Please read our Terms of Use before relying on a result for an important decision, and check with a qualified professional where money, health or legal matters are involved.

Boltly is free to use. We use basic analytics to learn which tools people need. Analytics cookies are only used if you agree to them, and you can change your choice at any time from the cookie settings link at the bottom of every page.

Found a mistake, or have an idea for a tool? We would like to hear from you. Visit the Contact page.