UD5 Toolkit
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.
Random Math Problem Generator - Online Arithmetic Drill
📐 Random Math Problem Generator
Online Arithmetic Drill – Practice addition, subtraction, multiplication & division
Frequently Asked Questions
It's an online tool that creates unlimited arithmetic problems for practice. You can customize operations, number ranges, and difficulty levels to generate drills that match your skill level.
Select the operation (addition, subtraction, multiplication, division, or mixed), choose your desired number range or difficulty level, and set the number of problems. Click "Generate Problems" and start answering. Submit to check your answers instantly.
Yes! After generating a problem set, use the Print button to get a clean printout without the settings panel. Perfect for classroom worksheets or offline practice.
Absolutely! Our random math problem generator is completely free. No sign-up required, and you can generate as many drills as you like.
Multiplication Grid Challenge – Online Fill the Times Table
Complete a 10x10 multiplication grid against the clock. A fun way to master times tables.
Mental Math Trainer - Online Timed Arithmetic
Solve random arithmetic problems under a time limit. Track your score and improve mental calculation. No data collected.
Interactive Multiplication Chart – Online Highlight Patterns
Click cells to see patterns, highlight multiples. Visual way to learn multiplication. Print empty grid.
Binary‑Decimal Conversion Quiz - Online Speed Drills
Test how fast you can convert between binary and decimal. Timed drills with increasing difficulty. Learn base‑2 fluency.
Disc Golf Putting Probability Calculator - Online C1X/C2 Stats
Estimate make probability of a putt based on distance and skill rating. For disc golf enthusiasts. Fun statistical tool, no data upload.
Probability Calculator - Online Odds & Combinatorics Tool
Compute probability for simple events, as well as permutations and combinations (nPr, nCr). Useful for statistics and game theory. Browser-based math.
Impossible Quiz - Online Tricky Question Challenge
Answer a series of deliberately confusing and trick questions. Lives system and funny wrong answers. Playful, no data stored.
Alien Language Generator - Online Random Con‑Lang Maker
Create a completely randomly generated alien script with fonts and syllable patterns. Translate your name into alien. Fun.
Math Expression Evaluator - Online Type & Calculate
Type a mathematical expression like 'sqrt(16)+sin(pi/2)' and get the result instantly. Supports popular functions. Local.
Geometry Area Quiz – Online Calculate Triangle, Circle, etc.
Random shapes appear; compute the area mentally. Multiple choice. For middle schoolers.
Visual Fraction Adder – Online Slice & Combine Pies
Drag pie slices to represent fractions and see them added together. Great for visual learners.
Resistors in Parallel Calculator - Online Multiple Branch Tool
Calculate the total resistance of up to 10 resistors in parallel. Enter values and see the combined resistance instantly. Local electronics helper.
Number Base Explainer - Online Learn Binary, Hex
Enter a decimal number and see detailed step‑by‑step conversion to binary, octal, and hex. For students.
Series & Parallel Resistor Network Solver
Build a combination resistor network by adding series/parallel groups and get total resistance. Visual circuit.
Shoelace Length Calculator – Online Eyelet Pairs & Pattern
Enter number of eyelet pairs and lacing style to find the correct shoelace length in inches/cm. Never buy too short.
Christmas Light String Calculator – Online Feet & Outlets
Enter roof line or tree height and get the length of light strings needed. Estimate power draw.
Word Permutation Solver - Online Anagram All Combinations
Enter letters and see every possible word permutation. Filter by dictionary words. Master your word game.
Final Exam Grade Calculator - Online What You Need to Score
Determine what score you need on your final exam to achieve your target overall grade. Enter current grade, weight, desired grade. Local only.
Lumber Calculator – Online Board Feet & Material Lists
Calculate board feet for dimensional lumber and generate a cut list with waste factor. Quick carpentry tool.
Cloze Test Generator - Online Remove Words for Learning
Paste a passage and automatically remove every nth word to create a fill‑in‑the‑blank exercise. For teaching and self‑study.
Voltage Divider Calculator - Online Two Resistor Output Tool
Calculate output voltage from a two-resistor voltage divider. Enter input voltage and resistances to see Vout. Includes circuit schematic. No data sent.
Polygon Area Calculator - Online Irregular Shape Tool
Calculate the area of an irregular polygon by entering its vertex coordinates. Uses the shoelace formula. Pure math.
Random Tattoo Idea Generator - Online Flash Sheet Picker
Get a random tattoo concept with style and placement suggestion. For fun and inspiration only. Not real art.
Language Cheat Sheet Generator - Online Phrase Card for Travel
Select a destination language and generate a printable mini phrasebook with essential greetings, directions, food, and emergency phrases. Local only.
A/B Test Significance Calculator - Online Simple Stats Tool
Check if your A/B test results are statistically significant using chi-squared test. Enter visitors & conversions for control/variant. Results in plain English.
Love Calculator - Online Fun Romance Compatibility Test
Enter two names and get a playful love compatibility percentage. Purely for entertainment! All calculation happens instantly in your browser.
Ellipse Drawing Tool - Online Interactive Geometry
Draw perfect ellipses by dragging focal points and a point on the curve. See the equation update dynamically. Educational.
Perfect Circle Drawing Challenge - Online Canvas Game
Try to draw a perfect circle freehand. Score based on roundness. Fun and addictive. No data sent.
Bike Gear Inch & Ratio Calculator - Online Cycling Tool
Calculate gear inches, meters of development, and speed ratio for any chainring/cog combination. For cyclists.