Study tools
Interactive tools for learning, practising and retaining knowledge.
About TeqSeq
TeqSeq is a growing collection of digital tools, applications and learning resources created to make everyday tasks simpler.
Interactive tools for learning, practising and retaining knowledge.
Practical experiments and resources for developers and technical work.
Purpose-built applications for everyday organisation and creativity.
Under the hood
A modern, typed Next.js application deployed through AWS Amplify Hosting.
View the architecture diagramsChangelog
Notable changes to how TeqSeq is built, deployed and hosted.
View all release notesUse a browser-based calculator with keyboard controls, parentheses, percentages, powers, square roots, reciprocal/sign controls and memory. Completed calculations are retained locally, can be restored or cleared, and can be downloaded as a TXT history.
Try the CalculatorPrepare authorized direct video file downloads in your browser with progress tracking, a 15-minute duration limit, and a save option when ready.
Try the Video DownloaderCreate random passwords in your browser, choose the length and character types, and copy the result. Each selected character type appears at least once.
Try the Password GeneratorDeveloper Tools now includes a Validators category for JSON, HTML, CSS, JavaScript and TypeScript — paste code and get a clear valid/invalid verdict, with the parser’s own error message (including line and column) shown when something is wrong. These reuse the same real parsers as the existing formatters (Prettier’s HTML, CSS, JS and TS parsers, plus native JSON.parse) rather than a second, separate validation layer.
Try the JSON ValidatorDeveloper Tools now includes a GraphQL Formatter, powered by Prettier’s GraphQL plugin — paste a messy or minified query and get it beautified with consistent indentation.
Try the GraphQL FormatterDeveloper Tools now includes an SVG Previewer. Paste SVG markup or load an example to see the artwork rendered in an isolated image preview.
Try the SVG PreviewerDeveloper Tools now includes minifiers for JSON, JavaScript, TypeScript, CSS, HTML and SVG, showing a size comparison for each result. JavaScript and TypeScript use real minification (via Terser) rather than simple whitespace removal, and TypeScript is first stripped of its types before minifying.
Try the JavaScript MinifierDeveloper Tools now includes a YAML Formatter, powered by Prettier — paste messy or inconsistently indented YAML and get it normalized correctly, since YAML’s whitespace-significant syntax needs a real parser rather than a simple indenter.
Try the YAML FormatterDeveloper Tools now includes JavaScript and TypeScript Formatters, powered by Prettier — paste messy or minified code and get it beautified correctly, including template literals, regular expressions and generics that simpler formatters often get wrong.
Try the JavaScript FormatterDeveloper Tools now includes a CSS Formatter — paste messy or minified CSS and get it beautified with proper indentation, nested @media blocks, and consistent spacing, with an example snippet to get started.
Try the CSS FormatterDeveloper Tools now includes an HTML Formatter — paste messy or minified HTML and get it beautified with proper indentation, with an example snippet to get started and a one-click copy for the result.
Try the HTML FormatterPages that take a moment to load, such as admin pages, now show a spinning TeqSeq gear animation flipping between "teq" and "seq" instead of a generic skeleton.
Developer Tools now includes an HTML Previewer alongside the JSON Formatter — paste HTML and see it rendered live in a sandboxed preview, with three example snippets to get started.
Try the HTML PreviewerTeqSeq now includes a dedicated Terms of Service page. The footer provides direct access to the Terms of Service alongside the Privacy Policy, Contact, and other legal information.
Read the Terms of ServiceTeqSeq 1.1.0 brings together the JSON Formatter developer tool, an admin view toggle for previewing internal-only content, dedicated Privacy Policy and Imprint pages for legal compliance, and a new Contact page with a validated form for reaching the team directly — alongside links out to the wider TeqSeq toolbox (Quiz Quest Hub and Nihongo Tech).
TeqSeq previously shipped as a static export synced to an S3 bucket, served through a hand-configured CloudFront distribution and deployed by running the AWS CLI by hand. It now runs on AWS Amplify Hosting compute: pushing to the main branch on GitHub deploys automatically, Amplify manages the CDN, TLS and caching without manual CloudFront invalidations, and the app runs as a full Next.js server instead of a static export, which unlocks server-only features such as dynamic metadata routes and request-time rendering.
See the before/after diagramThe creator
TeqSeq is an evolving home for practical software projects. Each tool explores an idea, solves a real problem or makes useful technology easier to access.