UD5 Toolkit
Speech Recognition Tester - Online Web Speech API Demo
Test your browser's built‑in speech recognition. Speak and see the transcribed text appear live. Must‑have for voice app devs.
Speech Dispatcher Tester - Online Explore All Voices
Speech Dispatcher Tester
Explore all available text-to-speech voices in your browser
Speech Controls
Loading voices...
Available Voices
No voices detected. Your browser might not support Speech Synthesis or voices haven't loaded yet.
Frequently Asked Questions
It's an online tool that lets you explore every text-to-speech (TTS) voice available in your browser via the Web Speech API. You can test different voices, adjust pitch, rate, and volume, and even listen to all voices sequentially.
Modern versions of Chrome, Edge, Firefox, Safari, and Opera support the Web Speech API. Some older versions or mobile browsers might have limited voice availability. For best results use the latest Chrome or Edge.
First, ensure your browser supports Speech Synthesis. Voices are loaded asynchronously; try clicking "Speak" once to trigger voice loading. On some operating systems you may need to install additional language packs. If you're on mobile, check your system TTS settings.
Yes, most voices are built into the operating system and work offline. However, some browsers (like Chrome) may use remote voices that require an internet connection. Local voices from your OS will always be available.
Speech Dispatcher is a server process in Linux that provides a common interface to speech synthesis. This online tool emulates the idea by letting you dispatch speech requests to various system voices through your browser.
Use the sliders in the control panel to set rate (speed), pitch, and volume. The values are applied to the currently selected voice. You can test immediately by clicking “Speak”.
The Web Speech API does not support direct audio export. However, you can use browser extensions or screen recording software to capture the synthesized speech if needed.
Speech Utterance Tester - Online Play Word by Word
Hear text spoken word by word with boundary events. See the exact index and character. Advanced TTS dev tool.
Speech Timer – Online Practice Presentations with WPM
Paste your speech, set time limit, and practice with a pacing indicator (words per minute). Refine delivery.
Speaker Test Tones - Online Left/Right Channel & Sweep
Play left‑only, right‑only, and frequency sweeps to test your speakers or headphones. Quick audio check.
Robots.txt Validator & Parser - Online Check Syntax
Paste robots.txt content and parse it to check validity, find disallowed paths. Educational SEO tool. Local processing.
:focus‑visible Tester - Online Keyboard‑Only Focus Ring
Compare :focus and :focus‑visible styling. See which one applies when using mouse vs. keyboard. Accessible focus management.
Robots.txt Validator - Online Check Syntax & Rules
Paste a robots.txt file and validate its syntax. See if a specific user‑agent can access a path. Essential for webmasters.
HTML Audio Visual Emphasis - Online Highlight Spoken Words
Combine TTS with text highlighting. See each word colored as it is spoken. For e‑learning content creation. Local.
Push Notification Tester - Online Generate & Receive
Register a service worker, subscribe to push, and send a test notification using a VAPID key pair. Step‑by‑step demo.
Meeting Speaker Timer - Online Countdown Per Agenda Item
Set a list of agenda items with allocated minutes. Advance through speakers and see remaining time visually. Keep meetings on track.
Coin Toss Probability Demonstrator – Online Long‑Run Simulator
Virtual flip coins thousands of times and see the heads/tails ratio converge to 50%. Interactive law of large numbers.
Audio Waveform Visualizer - Online See Your Sound
Visualize audio in real time from your microphone or uploaded audio file. See the waveform dance. Uses Web Audio API locally.
Random Yes No Decision Wheel - Online Spinner with Sound
Spin a colorful wheel that lands on Yes, No, or custom answers. Includes sound effects and adjustable probability. Local fun decision maker.
Random User Agent String Generator - Online for Testing
Generate a realistic, random user‑agent string for desktop, mobile, or bot. Perfect for API testing and scraping.
User Agent Parser - Online Browser & OS Detector
Paste a user agent string to get a human-readable breakdown of browser, operating system, and device. See your own current agent info automatically.
Robots.txt Generator - Online Create & Validate Robots File
Build a properly formatted robots.txt file with user-agent rules and sitemap location. Validate syntax in real time. Essential for webmasters.
Online Guitar Tuner - Browser Microphone Pitch Detection
Tune your guitar using the browser microphone. Detects pitch and shows deviation from standard tuning. No installation, pure client-side audio processing.
Random Animal Soundboard - Online Hear Real Calls
Click buttons to play real animal sounds: lion roar, bird tweet, dolphin click. Studio recorded. No load.
Online Metronome with Subdivisions - Precise Rhythm Trainer
Play a metronome with adjustable BPM, time signature, and subdivisions (eighth, triplet, sixteenth). Tap tempo and visual flash. Works offline for practice.
Audio Visualizer Bars - Online Live FFT Spectrum
Play an audio file or use mic to see real‑time frequency bars. Choose colors. Great for music videos. Canvas.
Regex Catastrophic Backtracking Tester - Online Benchmark
Test a regex against long strings and measure execution time. Detect catastrophic backtracking patterns. Visual warning if slow.
Random Sentence from Corpus - Online Paste & Generate
Paste your own text and generate a random sentence that mimics its style. Use for creative writing prompts or testing. Fully local.
Responsive Design Emulator - Online Test All Device Sizes
See your website inside iframes at multiple breakpoints simultaneously. Side‑by‑side responsive testing.
Potty Training Log – Online Record Accidents & Successes
Simple tracker to record potty attempts, successes, accidents. See patterns. Data stays local. Aids in toilet training journey.
Browser Screen Recorder - Online Record Tab & Download WebM
Record your screen, window, or tab with audio directly in the browser. Download the recording as a WebM file. No upload.
Browser Screen Recorder - Online Record Tab & Download WebM
Record your screen, window, or tab with audio directly in the browser. Download as WebM. No extension required.
HTML Minifier Comparison - Online See Savings Live
Paste HTML and see a before/after comparison of minified output. Check the byte savings. All local.
Online Metronome - Precise Beats per Minute & Time Signature
A precise online metronome with adjustable BPM, beat emphasis, and time signature. Works offline. Essential for musicians.
Plant Watering Reminder - Online Houseplant Care Scheduler
Set watering schedules for multiple plants with visual alerts. Shows which plants need water today based on last watered date. Data stored locally.
DOM Event Inspector - Online See All Event Listeners
Click any element on a demo page and see which events are attached. Visual debugger for event handling.