Small tools for the jobs that eat your afternoon.
I build these when a task I do by hand gets old. They run in your browser, they're free, and your files never leave your computer. — Douglas
Spreadsheets & CSV
Clean, split, merge and compare exported data. Your file never leaves your browser.
CSV Cleaner
Fix a messy spreadsheet export in a minute. Remove duplicates and blank rows, tidy emails, phone numbers and dates, and split, merge, rename or reorder columns.
CSV Splitter
Split one big CSV into smaller files by rows, file count, size or the values in a column, or pull a random sample. Every file keeps the header row.
CSV Merger
Combine several CSVs into one file. Merge strictly when the headers match, keep every column when they don't, or map columns by hand. You see the differences before you merge.
CSV Compare
Compare two CSVs by a key column. See what's only in one file, what changed cell by cell, and where the duplicates are. Row order doesn't matter.
Excel Merger
Combine .xlsx, .xls, .xlsm and .ods files into one workbook. Pick the sheet in each file, then line up the columns strictly, as a union, or by hand.
Use AI safely
Strip private details before you paste, and write prompts that keep you doing the thinking.
Privacy Filter
Paste text or open a spreadsheet and swap names, emails, phone numbers, addresses and account IDs for safe placeholders before you send it to an AI tool.
SDR Prompt Builder
The guide's Structure, Dialogue, Result method as a short form. Answer a few plain questions and get one careful prompt, three follow-ups, and a note on what to keep.
Calendars & schedules
Turn the lists you already have into calendar events — and leave the private columns behind.
For local businesses
Small, practical tools for shops, restaurants and service businesses.
Delivery Commission Calculator
See what the delivery apps' commission costs you per month and per year, how much of it you could keep with direct ordering, and when the switch pays for itself.
Review QR Card
Turn your Google review link or Place ID into a print-ready "Scan to leave us a review" card. Pick a size and colors, add your logo, then print at true size or save a 300 dpi PNG.
Apps
Full apps, built and published by OCN.
New guides and tools, by email.
One short note when something new ships — usually every few weeks, never more than that. Starts with the free SDR cheat sheet.