ROAS & Advertising Profit Calculator
Model return on ad spend, contribution margin, break-even ROAS, and estimated profit before overheads.
Free online tools
A growing library of practical utilities for advertising, design, search visibility, data and creative production. Each tool has its own page, can be bookmarked, and runs in a normal modern browser.
Showing all 10 tools
Advertising & marketing
UTM Campaign URL Builder
Create campaign tracking links with safely encoded UTM parameters and copy or export the finished URLs.
Google Ads Text Length Checker
Check responsive search-ad headline and description character counts against common limits, with bulk paste support.
Data & development
JSON Formatter & Validator
Parse JSON, locate syntax errors, format or minify it, and download the transformed result without uploads.
CSV to JSON Converter & Data Preview
Convert quoted CSV records to JSON or JSON objects back to CSV, with delimiter selection, validation, and downloads.
Private Text Difference Checker
Compare two passages line-by-line and highlight removed, added and unchanged lines without uploading the text.
Images & creative
Image Resizer & Format Converter
Resize images proportionally and export PNG, JPEG, or WebP using a private in-browser canvas.
WCAG Colour Contrast Checker
Calculate foreground/background colour contrast, preview readable combinations, and check common WCAG text thresholds.
SEO & development
SERP Title & Description Preview
Preview a prospective search result snippet, inspect metadata lengths and draft a more readable title and meta description.
Video & audio
SRT Subtitle Timing & VTT Converter
Shift subtitles forward or backward, rescale timings and export valid SRT or WebVTT files for video editing.
About this collection
These tools aim to solve small, concrete problems. Many process data locally without a file upload. Some features require JavaScript or modern browser support; results should be checked before professional or critical use. The collection will expand selectively—quality matters more than sheer page count.
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