40 tools · 7 categories · nothing uploaded
Calculators and file tools that show their working
TrueScalers publishes 40 free browser-based tools across 7 categories: calculators for mortgages, loans, percentages, BMI and grades; PDF tools that merge, split and compress; image tools that resize, compress and convert; converters, generators and developer utilities. Every tool computes inside the browser, so no figure, document or photograph is ever uploaded.
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Finance, health, date and academic calculators. Each page states the formula, defines every variable, and cites the authority the method comes from.
- Percentage calculator
- Mortgage calculator
- Loan calculator
- Car payment calculator
- Compound interest calculator
- Savings goal calculator
- Tip calculator
- Discount calculator
- Sales tax calculator
- BMI calculator
- Calorie calculator
- Body fat calculator
- Age calculator
- Date duration calculator
- Grade calculator
- GPA calculator
Length, mass, temperature, speed, volume and data storage. Every conversion factor is the exact internationally agreed definition, printed beside the result.
- Length converter
- Weight converter
- Temperature converter
- Speed converter
- Data storage converter
- Volume converter
Merging, splitting, compressing and building PDFs. Unlike every upload-based PDF site, your document is opened and rewritten inside this page — it never reaches a server, so there is nothing to leak and nothing to delete.
All PDF tools →Resizing, compressing and converting images, one at a time or in batches. Files are decoded and re-encoded by your own browser, so photos never leave your machine.
All image tools →Passwords, random numbers and UUIDs, drawn from the browser’s cryptographic random number generator. Nothing leaves the page.
All generators →JSON, Base64, URL encoding, SHA digests and regular expressions. Safe for real payloads and real secrets, because nothing you paste is transmitted or stored anywhere.
All developer tools →Counting and transforming text. Everything is processed in the page — paste a draft, a contract, or a private document without it leaving your machine.
All text tools →Why these tools are different
- Nothing leaves your browser
- Every calculation, every PDF and every photograph is processed as JavaScript on your own device. There is no API and no server-side compute. Salary figures, loan balances, medical scans and passport photos stay on your machine — unlike upload-based PDF and image sites, there is nothing to leak and nothing to delete.
- The formula is on the page
- Each calculator prints the expression it evaluates and defines every symbol in it. A result you cannot check is a result you cannot rely on, particularly for a mortgage or a medical screening figure.
- Sources are cited and dated
- Thresholds and constants come from named authorities — the WHO for BMI bands, NIST for unit definitions, the CFPB for lending disclosure, the IETF for identifier and encoding formats. Each page shows when it was last reviewed.
- No paywall, no watermark, no cap
- Free PDF and image sites typically cap file size, watermark the output, or limit you to a few files a day, because their costs scale with your uploads. These tools run on your hardware, so there is no cost to meter and no reason to restrict them.
Formulas and sources last reviewed . Read the methodology for how every calculation is derived.