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HIOS — Proyectos documentados y open sourceNext.js · Ant Design · mucho café
Local lab

Workbench

47 tools
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A clear catalog for validating, generating, inspecting, and testing from the browser.

Audio Lab

Tuning, reference tones and quick analysis for testing speakers, DACs and signal chains from the browser.

10 tools
  • Signal GeneratorTones, white/pink/brown noise, sweeps and L/R tests for speakers, DACs and audio chains.Local only
  • Instrument TunerMulti-instrument tuner (guitar, bass, ukulele, strings) with adjustable A4 and a clickable string diagram.Local only
  • Spectrum AnalyzerRealtime microphone FFT to inspect frequency energy from the browser.Local only
  • Level MeterRelative microphone meter for comparing loudness, noise floor and signal peaks.Local only
  • MetronomeConfigurable musical click with tempo, beats and subdivisions for practice or timing tests.Local only
  • Beat CounterEstimate BPM by tapping the pulse with clicks or the spacebar.Local only
  • Delay CalculatorConvert BPM to musical delay times and milliseconds to acoustic distance.Local only
  • Note · Frequency · MIDIConvert between musical note, frequency in Hz and MIDI note number, with tunable A4.Local only
  • Chiptune ComposerCompose retro video-game music in a piano-roll with synthesized 8-bit voices and export to .mid and .wav.Local only
  • Audio ConverterUpload an audio file and export it to WAV or MP3, all in the browser.Local only

Network Lab

DNS, certificates, subnets, domains and connectivity checks from one clear surface.

7 tools
  • DNS InspectorQuery live DNS records, including MX, TXT, NS, A, and AAAA, without leaving the workbench.Makes network calls
  • IPv4/Subnet CalculatorCalculate network, broadcast, mask, wildcard and usable hosts from CIDR.Local only
  • WHOIS / RDAPQuery public domain registration data with RDAP, the modern WHOIS replacement.Makes network calls
  • Certificate ExpiryInspect live TLS certificates, issuer details, and remaining validity before they become an outage.Makes network calls
  • Site CheckerMonitor URLs from the browser only, with local checks and desktop notifications.Makes network calls
  • URL Parser & BuilderParse URLs, inspect query params and build modified URLs — all in your browser.Local only
  • IPv6 Expand / CompressExpand and compress IPv6 addresses following RFC 5952, fully in the browser.Local only

Validation

Decode, inspect, and verify payloads, auth artifacts, DNS records, or TLS state before they reach production.

6 tools
  • Payload LabFormat, validate, and share JSON payloads without leaving the browser.Local only
  • Type CheckerValidate in the browser whether a JSON payload is assignable to a root TypeScript type.Local only
  • JWT PlaygroundInspect JWT headers, payloads, and expiration locally without sending the token anywhere.Local only
  • Hash & DigestGenerate SHA-1/256/384/512 digests (hex and base64) entirely in your browser.Local only
  • Usage DashboardAggregated metrics for top pages and tools by period and locale.Local only
  • HMAC GeneratorCompute HMAC SHA-1/256/384/512 from a key and message with Web Crypto.Local only

Generation

Produce useful strings, snippets, and other quick artifacts without leaving the browser.

14 tools
  • Object to TypesGenerate TypeScript interfaces and aliases directly from a real JSON object.Local only
  • Random String GeneratorGenerate quick strings for secrets, IDs, demos, or fixtures in one place.Local only
  • Encoder / DecoderBase64, base64url, hex and URL encode/decode (UTF-8) in your browser.Local only
  • UUID / ULIDGenerate UUID v4 and ULID identifiers in batches, in your browser.Local only
  • Mermaid DiagramsEdit and render Mermaid diagrams (flowchart, sequence, UML…) in your browser.Local only
  • Excalidraw DiagramsSketch UML and architecture diagrams visually, then keep/export your scene locally.Local only
  • Snippets ShelfStore quick notes, recipes, and frequent fragments locally.Local only
  • Markdown NotesLocal-first markdown notes with a live preview, in your browser.Local only
  • Pattern LessonsInteractive modern-pattern lessons with editable code and a sandboxed runner.Local only
  • Color ToolsConvert HEX, RGB, HSL; pick colors and inspect WCAG contrast ratios — all in your browser.Local only
  • Timestamp ConverterConvert Unix timestamps and date strings to ISO, UTC, relative and more formats.Local only
  • JSON Schema GeneratorInfer a JSON Schema from any JSON sample with format detection and required-field analysis.Local only
  • Image to Base64Convert images to data URIs, base64, CSS snippets or HTML img tags.Local only
  • Image ConverterUpload an image and export it to PNG, JPG or WEBP, all in the browser.Local only

Testing

Compare objects, inspect differences, and jump into embedded validation flows.

6 tools
  • Object ComparatorCompare two JSON objects and surface structural differences in seconds.Local only
  • Regex TesterTest regex patterns against multiline input with live highlight and group capture.Local only
  • Text DiffCompare two texts line by line (LCS) entirely in your browser.Local only
  • Cron ExpressionParse cron expressions and preview next run times with a field breakdown — no server needed.Local only
  • Number Base ConverterConvert between decimal, hexadecimal, binary and octal with a bit-field visualizer.Local only
  • CSV ⇄ JSONConvert CSV to JSON and back with RFC 4180 quoting and a configurable delimiter.Local only

Electronics

Quick hardware math — resistor color codes, Ohm's law and friends, next to the pinouts.

2 tools
  • Resistor Color CodeDecode 4 and 5-band resistor colors to a value, or build the bands from a value.Local only
  • Ohm's LawSolve voltage, current, resistance and power from any two known values.Local only

Reference

Fast lookups you reach for daily: HTTP status codes, ASCII/Unicode and more.

2 tools
  • HTTP Status CodesSearchable reference of HTTP status codes with category and meaning.Local only
  • ASCII / Unicode TableInspect characters and code points in decimal, hex, octal and binary.Local only

What this surface prioritizes

Clarity, contrast, and fast response before density.

Local-first and private

Payloads, notes, and state stay local whenever that makes sense. Less friction and real privacy.

Shareable sessions

When a workflow really matters, you can share it by URL instead of explaining ten manual steps.

Built for daily return

It is not trying to look like a demo. It is trying to solve real work with as little friction as possible.