Herramientas en línea
Herramientas gratuitas en el navegador para desarrolladores y estudiantes: SQL, JSON/YAML, regex, cron, hash, JWT, matemáticas y más.
Development
- SQL sandboxDesign your own database schemas, fill tables with data, and run SQL queries.
- HTTP request builderLight REST client: method, URL, headers, body, response — in the browser.
- JSON/YAML toolboxFormat, validate and convert JSON and YAML in both directions.
- JWT decoderDecode JWT header and payload, inspect claims and expiration — locally in browser.
- Diff checkerCompare two texts line by line with side-by-side highlights and unified diff.
- Regex checkerTest JavaScript regular expressions: live matches, groups, highlight, and replace preview.
- Git LabPractice branches, commits, merges, and conflict resolution in a Git simulator.
- Java PlaygroundRun a small Java subset in the browser: main, variables, loops, println — not a full JVM.
- Python PlaygroundRun Python in the browser (Skulpt): print, loops, functions, lists — not full CPython.
- ClipboardAccount-bound text cells: store snippets up to 3000 characters, lock sensitive notes, copy and paste in one click.
- FlowchartsCreate and save flowcharts: processes, decisions, and connections.
Infra & utilities
- CIDR calculatorCalculate subnet mask, network range, and host count from an IPv4 CIDR.
- Cron helperParse cron expressions and see field meanings plus the next run times.
- Hash generatorMD5, SHA-256, SHA-512 and HMAC from text or files — computed locally in your browser.
- UUID generatorGenerate UUID v4 and v7 in the browser: batch mode, formatting, copy and validate.
- Timestamp converterConvert Unix timestamp and date/time: seconds, milliseconds, ISO UTC and local time.
Design
Math & exams
- Math 1–6Elementary math: arithmetic, fractions with steps, percents, area and perimeter — in your browser.
- Math 7–11Algebra and graphs: linear & quadratic equations with steps, y = f(x) plot, Pythagoras and circle.
- OGE / EGEFull part-1 variants: OGE (19), EGE base (21), EGE profile (12). Answer check and solutions.
- SAT / ACT MathFull SAT Math (44) and ACT Math (60): multiple choice and grid-in, check and solutions.
- CalculatorBasic and scientific calculator in the browser: expressions, trig, powers, and constants.
- Quiz generatorBuild quiz templates from lesson questions: pick manually or auto-generate by difficulty, then save for future sessions.
Reference materials
- Elementary math formulasHandy formulas for grades 1–4: arithmetic, fractions, units, geometry, and percents.
- Secondary math formulas (grades 5–11)Reference for grades 5–11: algebra, quadratics, geometry, trigonometry, progressions, and coordinates.
- Physics formulas: MechanicsMechanics reference: kinematics, dynamics, statics, hydrostatics, work, energy, oscillations and waves.
- Physics formulas: Molecular physicsMolecular physics: amount of substance, kinetic theory of gases, ideal gas laws.
- Physics formulas: ThermodynamicsThermodynamics: internal energy, heat, phase changes, first law, heat balance, engine efficiency.
- Physics formulas: ElectrodynamicsElectrodynamics: electrostatics, DC circuits, magnetic field, induction, AC oscillations.
- IT dictionary561 IT terms in 9 topics: programming, networks, databases, security, cloud, AI, product management, and slang.
- Formula builderCreate a multi-line LaTeX formula card and drag it into a lesson.
Resources
- Image galleryUpload and store your images with descriptions and shareable links.
- Image placeholderDrag a placeholder into a lesson and describe what image should appear. Replace it later with a file upload or from Image gallery.
- Sound galleryUpload and store audio files with descriptions, groups and shareable links.
- Video galleryUpload and store video files with descriptions, groups and shareable links.
- Content StudioCreate and publish articles, guides, instructions, and other materials under your author URL.