Simple Desk Tools – Free Calculators, Size Charts & Text Converters
Quick calculators, size charts and text converters that just work. Pick a tool below.
- 100% free
- No sign-up
- Nothing uploaded
- No watermark
- No limits
- No catch
Paper Size Converter
A4, Letter, A5 and more in mm, inches and pixels at any DPI.
DPI Calculator
Pixels to inches and cm, print size to pixels, and print-quality check.
Aspect Ratio Calculator
Find the missing width or height for 16:9, 4:3 and any ratio.
Ring, Shoe & Hat Size Converter
International size charts for rings, shoes and hats.
Fancy Text Generator
Bold, italic, cursive and strikethrough Unicode fonts for Instagram bios.
CSV to Markdown
Convert CSV or TSV into a clean Markdown table, and back.
JSON to CSV
Flatten nested JSON into a spreadsheet-ready CSV, and back.
What is Simple Desk Tools?
Simple Desk Tools is a collection of free online tools that run entirely in your browser. There is no account, no upload, no watermark and no usage limit. Tools on this site:
- Aspect Ratio Calculator — Free aspect ratio calculator. Enter a width and height, then a new width or height, and get the missing value with the ratio locked. Presets for 16:9, 4:3, 1:1, 21:9, 9:16 and cinema ratios, plus common resolutions. Free, no sign-up, no upload.
- CSV to Markdown Table Converter — Convert CSV or TSV to a Markdown table instantly. Handles quoted fields, embedded commas and newlines, auto-detects the delimiter, aligns columns and previews the result. Also converts Markdown tables back to CSV. Runs in your browser. Free, no sign-up, no upload.
- DPI Calculator – Pixels to Inches, cm & Print Size — Free DPI calculator. Convert pixels to inches or cm at any DPI, work out how many pixels you need for a print size, or find the DPI of a photo and see whether it is good enough to print. Free, no sign-up, no upload.
- Fancy Text Generator – Bold, Italic, Strikethrough & Cursive Unicode Fonts for Instagram — Free fancy text generator. Type once and copy bold, italic, cursive, gothic, double-struck, strikethrough, small caps, bubble and upside-down Unicode text for Instagram, TikTok, Twitter and Discord. Runs in your browser. Free, no sign-up, no upload.
- JSON to CSV Converter – Flatten Nested JSON Online — Convert JSON to CSV in your browser. Flattens nested objects and arrays with dot notation, unions all keys, handles quoting, and converts CSV back to JSON with type inference. Free, no upload. Free, no sign-up, no upload.
- Paper Size Chart & Converter – A4, Letter, A5 in Pixels, mm, Inches — Paper size chart and converter for ISO A, B and C series, US Letter, Legal, Tabloid and photo sizes. Get dimensions in mm, cm, inches or pixels at any DPI, plus a visual size comparison. Free, no sign-up, no upload.
- Ring Size, Shoe Size & Hat Size Converter – International Chart — Convert ring sizes (US, UK, EU, Japan, mm), shoe sizes (US, UK, EU, cm for men, women and kids) and hat sizes (cm, inches, US/UK, S–XL). Full international charts plus a measure-and-convert tool. Free, no sign-up, no upload.
Simple Desk Tools vs. the usual suspects
| This tool | Typical "free" tool sites | |
|---|---|---|
| Price | Free, forever | Free tier, then paywall |
| Account | None — open the page and go | Sign-up or email required |
| Your files | Stay on your device; nothing is uploaded | Uploaded to their servers, kept for hours |
| Watermark | None | On the free tier |
| Limits | None — any size, any number of files | Daily caps and file-size limits |
| Speed | Instant — runs in your browser | Queue, upload, wait, download |
Our promise: no registration, no upsell, no "premium" button, no watermark, no file limits, and your files never leave your computer. The site is paid for by a couple of ads, nothing else.
Private by design
Every tool on this site is a single page that runs entirely in your browser. Your files are processed on your own device and are never uploaded to a server — close the tab and nothing is left behind. No accounts, no limits, no watermarks.