Most "free" online tools are free in exchange for your files. They upload everything you process to servers, train models on your data, and serve you ads based on your document contents.
These 21 tools are genuinely free — and your files never leave your browser.
Why browser-based tools are better
- Privacy: files processed locally, never uploaded
- Speed: no upload/download round-trip, results are instant
- Works offline: once the page loads, no internet needed
- Verifiable: open DevTools → Network to confirm zero uploads
All tools listed here run 100% in your browser using JavaScript and WebAssembly.
Image Tools
1. Image Compressor
Reduce JPG, PNG, and WebP file sizes by up to 80% without perceptible quality loss. Batch process up to 5 images. Quality slider per image with before/after size comparison.
2. Image Resizer
Resize images to exact pixel dimensions or choose from 8 social media presets (Instagram square, Twitter header, LinkedIn banner, etc.). Maintains aspect ratio with a lock toggle.
3. Image Converter
Convert between JPG, PNG, WebP, and BMP formats. Batch convert up to 5 images with per-image format selection.
4. Image Cropper
Crop images with preset aspect ratios (1:1, 16:9, 4:3, 3:2, 9:16) or draw any free selection. Real-time pixel dimensions displayed as you drag.
PDF Tools
5. PDF Merger
Combine up to 5 PDF files into a single document. Drag to reorder pages before merging. Page counts shown per file.
6. PDF Splitter
Extract page ranges, split into individual pages, or create multiple custom ranges from a single PDF. Multi-file outputs download as a ZIP.
7. PDF Compressor
Reduce PDF file size using structural compression via pdf-lib. Four compression levels with before/after size display.
Developer Tools
8. JSON Formatter
Format, validate, and minify JSON instantly. Syntax-highlighted output. Error messages for invalid JSON.
9. Base64 Encoder / Decoder
Encode text or files to Base64 and decode back. Supports standard and URL-safe Base64. File-to-Base64 without upload.
10. URL Encoder / Decoder
Percent-encode URLs and query strings using encodeURIComponent or encodeURI. Decodes back with one click.
11. HTML Encoder / Decoder
Convert <, >, &, ", ' to HTML entities and back. Includes attribute-safe encoding mode.
12. Regex Tester
Test JavaScript regular expressions with live color-highlighted match visualization. Shows capture groups, supports replace mode, and includes 6 preset patterns.
13. CSS Minifier & Formatter
Minify CSS by stripping whitespace and comments, or beautify minified CSS. Live processing with size reduction stats.
14. Markdown to HTML
Convert Markdown to HTML with a live split-pane preview. Toggle between rendered and HTML source views.
15. Number Base Converter
Bidirectional conversion between binary, octal, decimal, and hexadecimal. Includes 8, 16, and 32-bit representations with two's complement for negative numbers.
16. Unix Timestamp Converter
Live current timestamp counter. Convert timestamps to dates in any IANA timezone. Auto-detects seconds vs. milliseconds.
17. Password Generator
Generate cryptographically secure passwords using crypto.getRandomValues() — not Math.random(). Custom length and character sets.
Text Tools
18. Word Counter
Real-time word, character, sentence, and paragraph counting. Reading time estimate and keyword density analysis.
19. Text Case Converter
Convert between UPPERCASE, lowercase, Title Case, Sentence case, camelCase, and snake_case instantly.
20. Lorem Ipsum Generator
Generate randomized Lorem Ipsum by paragraphs, sentences, or words. 1 to 100 units, with optional classic opening sentence.
Color Tools
21. Color Picker & Converter
Pick colors with the native OS color picker. Convert between HEX, RGB, HSL, and CMYK. WCAG contrast ratio checker included.
How to verify none of these tools upload your files
- Open any tool page
- Press F12 to open Chrome DevTools
- Click the Network tab
- Use the tool (upload a file, process it, download the result)
- Check the network requests — you will see zero file upload requests
This is auditable, verifiable proof. Not a privacy policy — actual network behavior.