Most online tool sites upload your files to a stranger's server and call it “free.” We do not. Every tool here runs locally in your tab — no upload, no account, no aftertaste.
Privacy as architecture
Your files never leave the tab
Most tools here use no server at all. The ones that do (link checks, OG previews) only handle URLs — never your files.
No accounts. Ever.
Open, use, close
We do not ask for your email, build a profile, or remember you between visits. There is nothing to log into.
Free, on purpose
Funded by ads, not your data
A small ad pays for hosting. We do not sell anything, upsell anything, or watermark anything to make you upgrade.
The ones people open most often.
Generate QR codes with custom colors, rounded corners, and logo embed.
Merge multiple PDF files into one document.
Paste your JSON and instantly format, validate, or minify it.
Compress images up to 90% smaller without losing quality.
Generate strong, random passwords with customizable length and character sets.
Pick colors, generate harmonious palettes, and export as HEX, RGB, or HSL.
Notes from the team — engineering, design, the occasional opinion.
When you upload a PDF to a stranger's server, you're handing them every word, signature, and number on the page. Here's why we refused to build it that way.
April 25, 2026 · 8 min read
DesignWhy “4.5:1” is not a slider value, why averaging RGB does not work, and what the new APCA model fixes.
April 22, 2026 · 7 min read
EngineeringThree identifier formats, three different bets on what matters. Pick the wrong one and the cost shows up months later as either ugly URLs or a slow database.
April 18, 2026 · 9 min read
Merge, split, and convert PDFs. Free and client-side.
Compress, convert, crop, resize, and watermark. Runs in your browser.
Compress images up to 90% smaller without losing quality.
Convert images between PNG, JPG, WebP, BMP, and GIF instantly in your browser.
Crop images with preset aspect ratios or freeform selection.
Resize photos to exact dimensions with aspect ratio lock.
Add text or logo watermarks to photos with custom position, opacity, and tiling.
Convert HEIC/HEIF photos from iPhone to universal JPG format.
Convert SVG files to high-resolution PNG at any scale.
Generate favicons at every size from any image.
Drop a screenshot and frame it in a device mockup — iPhone, MacBook, iPad, Browser, or Android.
Generate placeholder images with custom dimensions, colors, and text.
JSON, regex, hashing, encoding, and debugging utilities.
Paste your JSON and instantly format, validate, or minify it.
Convert JSON arrays of objects to CSV with auto-detected headers.
Encode text or files to Base64, or decode Base64 back to text and files.
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes for text or files.
Live regex tester and debugger.
Encode or decode URL strings in real time.
Generate v4 UUIDs instantly.
Compare two texts side by side with line-by-line diff highlighting.
Build cron expressions visually or paste one to decode it.
Generate a robots.
Generate SEO meta tags, Open Graph, and Twitter Card HTML.
Preview how your link appears on Facebook, Twitter, LinkedIn, Discord, and Slack.
Check if your domain's email authentication is set up correctly.
Convert text to binary, hexadecimal, and decimal byte values in real time.
See your public IP address, location, ISP, and timezone instantly.
Convert Markdown to HTML with a live preview.
Full-featured Markdown editor with toolbar, live preview, word count, and export.
Convert between Unix timestamps and human-readable dates.
Colors, gradients, shadows, and layout helpers.
Pick colors, generate harmonious palettes, and export as HEX, RGB, or HSL.
Build linear and radial CSS gradients visually.
Build CSS box shadows visually with live preview.
Calculate aspect ratios and resize dimensions while keeping proportions.
Test color combinations against WCAG 2.
Word counts, case conversion, passwords, QR codes, and more.
Count words, characters, sentences, paragraphs, and reading time in real-time.
Convert text between UPPERCASE, lowercase, Title Case, camelCase, snake_case, kebab-case, and more.
Generate lorem ipsum placeholder text by paragraphs, sentences, or words.
Generate strong, random passwords with customizable length and character sets.
Generate QR codes with custom colors, rounded corners, and logo embed.
Transform text into 18 Unicode styles — bold, cursive, gothic, aesthetic, and more.
Create and download professional PDF invoices for free.
Create a professional HTML email signature with your name, title, company, phone, and social links.
Every couple of weeks, you need a small thing done. Merge two PDFs. Compress a screenshot before emailing it. Pull the colors out of an image. Format an unholy block of JSON. The default way to handle this is to type the problem into Google, click the first result, drag your file in, and hope.
What that file does next is mostly invisible to you. It uploads to a server somewhere. It gets processed. It might get deleted in an hour, or it might get retained for analytics, or it might get fed into an ad network's profile-building pipeline. You took the operator at their word, because there was no other option.
Persimmon is the version of those tools that decided not to move your file at all. The PDF tools, the image tools, the text tools — almost everything here runs entirely inside the browser tab you have open. The byte stream of your document does not cross a network boundary, because there is no network call to make. We could not see your file if we wanted to.
That decision shaped what we will and will not build. We do not have OCR yet, because the practical client-side options are slow. We do not have document templates, because templates need persistence and persistence needs accounts. We are fine with those trade-offs, because the alternative is the model we specifically did not want to repeat.
The blog has more on the engineering decisions behind individual tools — the privacy model behind the PDF tooling, the math behind the contrast checker, why we picked v4 UUIDs as the default for the ID generator. If you want the long version, it is over here.