About Plaintools

Last updated 7 September 2026.

What this is

Plaintools (https://plaintools.io) is a public set of browser utilities. Convert a file, generate markup, check an identifier, or run a calculator without creating an account and without sending the input to a server. The HTML is the product; there is no app store listing and no upload API.

Why the tools stay in the tab

Paste-bins and “free converters” often take the file. These pages read bytes and text with the browser’s own APIs (File, Canvas, Web Crypto, WebAssembly). That is the whole trust model. Host logs still see the URL you requested. That is documented on the privacy page, but the contents of a paste box or a dropped HEIC are not posted anywhere by this origin.

How a tool is documented

Each live tool has a title, an explainer, a worked example, FAQs, and a recipe that describes the actual algorithm. Agents can read the same catalog as /llms.txt and per-tool markdown (linked as text/markdown from the HTML). The markdown index is a copy of that catalog, not a second set of answers. Registry tests in the repo check that recipes, FAQs, and routes stay in sync.

What the numbers are not

Finance, shipping, and build calculators are estimates from published formulas or public fee schedules. They are not advice, a quote, or a substitute for the carrier, lender, or supplier. If a figure is wrong, treat the FAQ and the markdown recipe as the spec of what the page computes, then check the official source before you spend money.

Who to contact

There is no account, no ticket inbox, and no newsletter. The terms are as-is. If you need a tool that is not listed, the category hubs below are the current scope.

Read the guides, or browse by job: SEO · Dev · Text · Convert · Checkers · Finance · Build · Shipping.