Generate arithmetic, geometric, and custom number sequences with sums. Fill spreadsheets and test series — free, local, no signup.
Generate random times with 24-hour and 12-hour outputs. Schedule surprise drills and test fixtures — free, local, no signup.
Generate random sentences for writing prompts, test data, and brainstorming. Break writer's block in one click — free, local, no signup.
Fill null (empty) cells in CSV data with a custom fill value. Clean datasets for analysis and migration — local processing, free, no signup.
Generate placeholder images by URL with custom size, text, and colors — wireframes that look intentional. Fill layouts before assets arrive — local generation, free, no signup.
Generate random MAC addresses for labs and testing — pure random hex, no OUI or unicast-bit management. Fill virtual networks credibly — local generation, free, no signup.
Arithmetic (+step), geometric (×ratio), and custom (n + n×r) progressions with sum totals. Test data and homework both covered.
Hundreds of terms per run locally. Million-term series belong in scripts with streaming output.
Yes — start, step, and count define any linear series. Geometric needs ratio instead of step.
No — generation runs locally in your browser. Nothing leaves your device.
Start 2, step 2, count 10 gives 2, 4, through 20 with the panel reporting sum 110 and count 10. Geometric mode multiplies by the ratio instead; Custom uses n + n x r.
Random Number Generator
Generates random integers within a user-defined min-max range with optional unique and sorted output. Uses the browser random number generator — fine for games, raffles, and sampling, not for security secrets. Input never leaves your device — everything runs locally in your browser.
Counter Tool
Simple tap counter with increment, decrement, and reset — reps, inventory, headcounts. Count 200 items without losing place — free, local, no signup.
Last updated October 2026