About TrueScalers

What TrueScalers covers

The library is organised into 7 categories, each built around a single class of problem rather than a grab-bag of unrelated widgets.

Calculators 16 tools

Finance, health, date and academic calculators. Each page states the formula, defines every variable, and cites the authority the method comes from.

Converters 6 tools

Length, mass, temperature, speed, volume and data storage. Every conversion factor is the exact internationally agreed definition, printed beside the result.

PDF tools 4 tools

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.

Image tools 3 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.

Generators 4 tools

Passwords, random numbers and UUIDs, drawn from the browser’s cryptographic random number generator. Nothing leaves the page.

Developer tools 5 tools

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.

Text tools 2 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.

What these tools solve

Most calculations people need are not hard, but they are easy to get wrong: a rate applied monthly instead of annually, a unit converted with a rounded constant, a percentage change computed against the wrong base. TrueScalers exists to make the correct method visible rather than hidden behind a result.

A number you can check

Every tool shows the formula it used alongside the result, so the output can be verified by hand rather than taken on trust. Where a figure depends on an assumption — a compounding period, a rounding rule, a threshold — the assumption is stated on the page.

An answer without an account

There is no sign-up, no paywall, no trial and no email capture on any tool. A visitor arriving from a search result reaches a working tool immediately, and the result updates as values are typed rather than behind a submit step.

Files that never leave the device

The PDF and image utilities process files entirely in the browser using the same JavaScript engine that renders the page. A document merged or an image resized here is never uploaded, which makes the tools usable for material that could not be sent to a third-party server.

Method, not just output

Each page carries a worked example with real numbers and a set of self-contained questions covering the edge cases the formula is most often misapplied to. The intent is that a visitor leaves understanding the calculation, not merely holding its answer.

How the tools run

Every calculation on TrueScalers executes as JavaScript on the visitor's own device. There is no API, no server-side compute and no telemetry attached to any figure entered into a tool. Salaries, loan balances, body measurements, documents and images are processed in the browser and discarded when the tab closes.

This is an architectural property rather than a promise: the pages are statically generated and ship no code capable of transmitting an input value. See the privacy policy for the full detail.

How these tools are built

Every formula is sourced

No calculation is implemented from memory. BMI thresholds come from the World Health Organization, unit definitions from NIST and the BIPM, lending disclosure rules from the US Consumer Financial Protection Bureau, and identifier formats from IETF RFCs. Each tool page links to the sources it relies on.

Every calculation is unit-tested

Calculation logic lives in pure functions with no dependency on the interface, and each is covered by tests asserting known-correct values, boundary conditions and inverse round-trips. A formula that cannot be tested independently of the page it appears on cannot be trusted.

Content is checked against the code

The figures quoted in each worked example are computed with the same functions the tool runs, not written by hand. Automated checks also enforce that every FAQ is self-contained, every source uses HTTPS, and every related-tool link resolves.

Review dates are real

The date on each tool page is the date the formula and its sources were last verified, and it is reviewed quarterly. A stale date is worse than no date, so it is only updated when a genuine review has taken place.

The derivation and source for every formula on the site is documented on the methodology page.

How the site is funded

TrueScalers is funded by display advertising. Ads are placed below the fold, never between a visitor and a result, and never inside the tool itself. No advertiser has any influence over which tools exist or what any page says. Ad slots reserve their height before loading so that filling them shifts no content, and the ad script is deferred until after the page is interactive.

Values entered into any tool are never used for advertising, because they never leave the browser in the first place.

Corrections

If a result looks wrong, it may well be. Email syedaqeel185@gmail.com with the tool name and the inputs used, and the calculation will be re-derived against its cited source. Confirmed errors are fixed and the affected page's review date is updated the same day.