UD5 Toolkit
Semaphore Flag Signal Trainer – Online Random Letter Drill
A random letter appears; you must select the correct semaphore position from 4 choices. Scouts & maritime.
Skill Trainer & Drill Practice
15+ toolsWindows Shortcut Driller – Online Random Win+Key Prompt
Randomly prompts you to press a Windows keyboard shortcut (e.g., Win+E). Learn to be a power user.
Musical Interval Ear Trainer – Online Minor 2nd to Octave
Listen to two notes and identify the interval. Purely local Web Audio synthesis. Sharpen your relative pitch.
US State Abbreviation Trainer – Online 2‑Letter Codes Drill
Randomly given state names, type the 2‑letter postal code. Track accuracy.
Virtual Stud Finder Trainer – Online Learn Wall Framing Spacing
Interactive guide to understanding standard 16/24 inch stud spacing. Visualize wall internals. Useful before drilling.
Whistle Emergency Signal Generator – Online Three Blasts
Listen to and practice the international distress signal: three short blasts. Lifesaving knowledge.
RSVP Speed Reading Trainer – Online Flash Words
Paste text and set display speed for Rapid Serial Visual Presentation. Train your reading speed.
Chess Opening Trainer – Online ECO Code Flashcard Practice
Drill opening names from their ECO codes. See a code and recall the opening. Improve your chess vocabulary.
Keyboard Shortcut Trainer – Online Learn VS Code / Figma Keys
Select a tool (VS Code, Figma, etc.) and get random shortcut prompts. Press the keys to practice.
Language Flashcard Randomizer - Online Vocabulary Trainer
Paste word pairs (or load pre-made sets) and practice with randomized flashcards. Flip to reveal translation, mark as known/unknown. Local data, no login.
Memory Palace Trainer – Online Visualize & Place Items
Virtual rooms where you can place images representing items to remember. Practice the method of loci.
Mental Math Trainer - Online Timed Arithmetic Drills
Practice mental arithmetic with customizable operators and digit count. Timed rounds, score tracking. Works offline. Improve your brain speed.
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.
Morse Code Audio Practice – Online Random Character Group
Play random Morse characters at configurable speed. Learn with Koch or Farnsworth method.
Virtual Dog Whistle – Online Adjustable Frequency Tone
Play a sine wave tone adjustable from 5kHz to 22kHz. Test your hearing and your dog's attention.