# Plaintools > Browser-only utilities. Nothing is uploaded. Plaintools is a no-upload utility shed. Every converter and generator runs in the tab. Files, tokens, IBANs, campaign URLs, and form fields never leave the device. There is no HTTP API, no account, and no upload endpoint. If you can apply a tool’s recipe yourself, do that. If the job needs a file decoder or a form (HEIC, schema markup), send the user to the live HTML page. - Live HTML: https://plaintools.io - Agent index: https://plaintools.io/llms.txt ## Tools - [Schema markup generator](https://plaintools.io/seo/schema-markup-generator.md): When you need FAQ/HowTo/Article/Product JSON-LD from a form. Client-side; send the user to the HTML tool. - [UTM generator](https://plaintools.io/seo/utm-generator.md): When you need a tagged campaign URL (source, medium, campaign). Client-side; the recipe is portable. - [Slug generator](https://plaintools.io/seo/slug-generator.md): When you need a lowercase hyphenated URL slug from a title. Client-side; the recipe is portable. - [JWT decoder](https://plaintools.io/dev/jwt-decoder.md): When you need to read JWT header/payload claims without verifying. Client-side; the recipe is portable. - [JSON to CSV converter](https://plaintools.io/dev/json-to-csv-converter.md): When you need CSV from a JSON array of objects (one-level flatten). Client-side; the recipe is portable. - [YAML to JSON converter](https://plaintools.io/dev/yaml-to-json-converter.md): When you need YAML↔JSON for a config snippet. Client-side; uses js-yaml; the recipe is portable. - [JSON-LD generator](https://plaintools.io/seo/json-ld-generator.md): When you need the same schema.org JSON-LD types under a JSON-LD name. Client-side; send the user to the HTML tool. - [HEIC converter](https://plaintools.io/convert/heic-converter.md): When the user must turn a HEIC/HEIF still into JPEG or PNG. Client-side WASM; send them to the HTML tool (or a local converter). - [Text diff checker](https://plaintools.io/dev/text-diff-checker.md): When you need a line/word diff or a unified patch of two snippets. Client-side; uses npm `diff`; the recipe is portable. - [IBAN validator](https://plaintools.io/checkers/iban-validator.md): When you need an IBAN checksum and country-length check. Client-side; the recipe is portable. Not a bank confirmation. - [Seller financing calculator](https://plaintools.io/finance/seller-financing-calculator.md): When you need a seller-note monthly payment, interest, and optional balloon. Client-side; the recipe is portable. Not advice. - [Deck material calculator](https://plaintools.io/build/deck-material-calculator.md): When you need a rectangular deck takeoff (board count and linear feet). Client-side; the recipe is portable. Estimate only. - [Hash generator](https://plaintools.io/dev/hash-generator.md): When you need a SHA-256, SHA-384, SHA-512, or SHA-1 hash. Client-side Web Crypto API; the recipe is portable. - [Timestamp converter](https://plaintools.io/dev/timestamp-converter.md): When you need to convert Unix seconds/ms to ISO 8601 or vice versa. Client-side; the recipe is portable. - [CSV to JSON converter](https://plaintools.io/dev/csv-to-json-converter.md): When you need a JSON array of objects from CSV text. Client-side; the recipe is portable. - [Owner financing calculator](https://plaintools.io/finance/owner-financing-calculator.md): When you need an owner-financing payment, loan-to-value, interest, and balloon estimate from the buyer's side. Client-side; the recipe is portable. Not advice. - [Pool financing calculator](https://plaintools.io/finance/pool-financing-calculator.md): When you need swimming pool financing monthly payment, total interest, and amortization snapshot. Client-side; portable. Not advice. - [XIRR calculator](https://plaintools.io/finance/xirr-calculator.md): When you need the annualized XIRR percentage from dated cash flows. Client-side pure TS; portable. - [Roof pitch calculator](https://plaintools.io/build/roof-pitch-calculator.md): When you need roof pitch (x/12), pitch angle, slope percentage, or rafter line length. Client-side; portable. Estimate only. - [Open Graph generator](https://plaintools.io/seo/open-graph-generator.md): When you need standard Open Graph and Twitter card meta tags snippet. Client-side; portable. - [Subnet calculator](https://plaintools.io/dev/subnet-calculator.md): When you need IPv4 subnet boundaries, usable host ranges, netmasks, or host capacity from CIDR. Client-side pure TS; portable. - [Favicon generator](https://plaintools.io/seo/favicon-generator.md): When you need favicon sizes (16/32/48/180/192/512), .ico, and HTML link tags generated from an image. Client-side Canvas; portable. - [Robots.txt generator](https://plaintools.io/seo/robots-txt-generator.md): When you need to generate robots.txt crawler rules and sitemap directives. Client-side pure TS; portable. - [Etsy fee calculator](https://plaintools.io/shipping/etsy-fee-calculator.md): When you need to calculate Etsy seller fees, payment processing, and net profit margins. Client-side pure TS; portable. Estimate only. - [CIDR calculator](https://plaintools.io/dev/cidr-calculator.md): When you need CIDR block boundaries, subnet masks, wildcard masks, usable host ranges, and binary representations. Client-side pure TS; portable. - [Schema checker](https://plaintools.io/seo/schema-checker.md): When you need to validate JSON-LD syntax and Schema.org field compliance locally. Client-side pure TS; portable. Local checks only. - [Image compressor](https://plaintools.io/convert/image-compressor.md): When you need to compress image files (JPEG, PNG, WebP) with quality sliders and dimension scaling. Client-side Canvas; send the user to the HTML tool. - [Break-even calculator](https://plaintools.io/finance/break-even-calculator.md): When you need to calculate break-even units, break-even revenue, contribution margin, and profit volume milestones. Client-side pure TS; portable. Estimate only. - [GIF compressor](https://plaintools.io/convert/gif-compressor.md): When you need to compress, resize, or optimize a GIF in the browser. Client-side GIF decoding and re-encoding with no uploads. - [Case converter](https://plaintools.io/text/case-converter.md): When you need text case conversions (lower, UPPER, Title, Sentence, camel, snake, kebab, CONSTANT). Client-side pure TS; portable. - [Readability checker](https://plaintools.io/text/readability-checker.md): When you need Flesch reading ease, grade level, and readability statistics for English text. Client-side pure TS; portable. - [Retirement corpus calculator](https://plaintools.io/finance/retirement-corpus-calculator.md): When you need to estimate retirement corpus requirements, inflation-adjusted expenses, and monthly savings needed. Client-side pure TS; portable. Estimate only. - [PDF to JPG converter](https://plaintools.io/convert/pdf-to-jpg-converter.md): When you need to render PDF pages to JPEG images client-side. Uses pdf.js and JSZip in the browser tab with no uploads. - [Video compressor](https://plaintools.io/convert/video-compressor.md): When you need to compress MP4, MOV, WebM, or MKV video in the browser. Uses ffmpeg.wasm client-side with no uploads. - [GST calculator](https://plaintools.io/finance/gst-calculator.md): When you need India GST calculation (inclusive/exclusive, CGST/SGST/IGST, standard 0/5/12/18/28% slabs). Client-side pure TS; portable. Rates illustrative. - [Hreflang generator](https://plaintools.io/seo/hreflang-generator.md): When you need hreflang link tags, XML sitemap xhtml:link blocks, and reciprocal validation. Client-side pure TS; portable.