All free online tools and calculators

Measure elapsed time and record individual lap results.

Alternate work, rest, and repeat rounds.

Set a labeled one-time alarm in your browser.

Display the current time in a large 12- or 24-hour format.

Count the days between today and an event or deadline.

Keep a steady, adjustable musical tempo.

See remaining time at a glance with a clear visual dial.

Use calm motion to show time without stressful digits.

Display an exam title, instructions, and countdown.

Use green, warning, and overtime zones while presenting.

Build balanced random groups from a list of people.

Shuffle people into numbered seating positions.

Visualize surrounding volume using your device microphone.

Signal go, wrap-up, or stop with a large color display.

Track scores for two teams with clear controls.

Track several independent counts at the same time.

Pick names or items fairly without repeats.

Generate a random whole number within a custom range.

Spin a reusable wheel of names or choices.

Roll one to six fair virtual dice.

Make a quick random heads-or-tails choice.

Reveal a playful random answer to a simple question.

Run a randomized four-lane race.

Alternate focused work sessions and reset breaks.

Plan and run a timed multi-step routine.

Follow calm visual cues for paced breathing.

Find percentages, percentage change, and proportions.

Convert common length, weight, and volume units.

Add, subtract, multiply, and divide fractions.

Calculate mean, median, mode, and range.

Calculate increase and percentage growth between two values.

Calculate decrease and percentage reduction between two values.

Simplify a ratio and scale it to another quantity.

Evaluate common powers, roots, logarithms, and trigonometric functions.

Calculate area for common two-dimensional shapes.

Calculate volume for common three-dimensional shapes.

Convert between Fahrenheit, Celsius, and Kelvin.

Calculate pace, speed, distance, or finish time.

Estimate monthly payments and total interest.

Estimate payoff time and total interest cost.

Project compound growth with optional recurring contributions.

Compare monthly income, expenses, and money remaining.

Calculate a tip and split the total fairly.

Compare package prices to find the better value.

Calculate sale price and savings after a percentage discount.

Estimate an affordable home price from income, debts, rate, and down payment.

Estimate principal and interest for a fixed-rate mortgage.

Compare estimated monthly renting and homeownership costs.

Estimate a savings target from essential monthly expenses.

Calculate the share of gross monthly income used for debt payments.

Compare total assets and liabilities to calculate net worth.

Estimate the monthly amount needed to reach a savings target.

Project future retirement savings from current balance and contributions.

Calculate gross profit and profit margin from revenue and cost.

Calculate selling price, profit, and markup from product cost.

Find the sales volume and revenue needed to cover fixed and variable costs.

Measure return on ad spend, profit, and customer acquisition cost.

Calculate total production cost and cost for each unit.

Estimate the hourly rate needed to cover income, overhead, taxes, and billable time.

Calculate marketing and sales cost for each new customer.

Project monthly and annual recurring subscription revenue.

Compare cash received and cash paid to estimate net cash flow.

Convert an hourly wage into weekly, monthly, and annual pay.

Calculate commission and total pay from sales performance.

Measure how often inventory is sold and replaced.

Measure advertising revenue returned for every dollar spent.

Estimate wall area and gallons of paint needed for a room.

Estimate flooring area, waste allowance, and package quantity.

Calculate rectangular area and total multiple spaces.

Estimate tile count from room and tile dimensions with waste.

Estimate cubic yards of concrete for a slab.

Estimate cubic yards of mulch from bed area and depth.

Estimate topsoil volume from area and depth.

Estimate a move from distance, home size, labor, and supplies.

Estimate electricity use and operating cost for an appliance.

Estimate roof area, waste, and shingle squares.

Estimate fence panels, posts, and project length.

Estimate deck area and board quantity.

Estimate wallpaper rolls from room dimensions and roll coverage.

Estimate a basic cooling capacity range from room area.

Count words, characters, sentences, and paragraphs.

Convert text to upper, lower, title, or sentence case.

Remove repeated lines while preserving the first occurrence.

Sort lines alphabetically, numerically, or in reverse.

Identify the most frequently used words in text.

Normalize spaces, blank lines, and common formatting problems.

Compare two blocks of text and summarize line differences.

Estimate reading level from words, sentences, and syllables.

Calculate a score percentage and letter grade.

Combine category scores using custom weights.

Estimate reading and speaking time from word count.

Enter classroom content once and create quizzes, answer keys, worksheets, flash cards, word searches, matching exercises, and study guides.

Create a printable short-answer worksheet from prompts.

Create printable study cards from terms and definitions.

Generate a printable word-search puzzle from a word list.

Choose students fairly without repeats.

Run a large classroom countdown with an activity label.

Create a clear scoring rubric with criteria and performance levels.

Format basic website, book, and article citations.

Organize topics, key points, and questions into a printable study guide.

Build a focused, classroom-ready lesson from objectives through closure and assessment.

Turn a topic into clear, measurable learning objectives teachers can review and revise.

Map lesson activities and evidence of learning to teacher-selected standards.

Plan supports, access points, and extensions for a classroom activity.

Create a concise schedule, procedure guide, and lesson plan for a substitute teacher.

Create quick printable checks for understanding at the end of a lesson.

Create grade-appropriate writing prompts by topic, purpose, and format.

Create vocabulary lists, definitions, examples, and practice activities.

Track teacher-entered progress exclusively on this device, with local export and clear controls.

Analyze score distributions and learning gaps locally without uploading student information.

Review teacher-entered attendance patterns locally without server storage.

Draft clear family messages while keeping entered details exclusively on the teacher's device.

Draft constructive, editable progress comments locally for teacher review.

Create a clear classroom newsletter for printing or local PDF export.

Prepare and retain conference notes exclusively on the teacher's device.

Create and rotate practical classroom responsibilities.

Track classroom supply quantities locally on the teacher's device.

Scale every ingredient for a different number of servings or batch size.

Convert common kitchen volumes into cups, tablespoons, teaspoons, and milliliters.

Convert oven temperatures between Fahrenheit, Celsius, and gas-mark estimates.

Calculate ingredient percentages from total flour weight.

Calculate hydration, total dough weight, and ingredient percentages.

Scale batter by comparing round or rectangular pan areas.

Add ingredient, packaging, labor, and overhead costs for a recipe batch.

Calculate cost per serving, menu price, and food-cost percentage.

Estimate total food quantity from guests and portion size.

Add preparation, cooking, resting, and buffer time to plan when to start.

Find practical replacements for common cooking and baking ingredients.

Track food quantities and review dates so ingredients get used instead of forgotten.

Turn a weekly meal plan into one combined, printable shopping list.

Look up minimum internal cooking temperatures for common foods.

Run several independently labeled cooking timers on one screen.