2026-09-09

65 Free Developer Tools That Run Entirely in Your Browser

Most "online tool" sites are one tool per domain, each with its own ads, its own upload-to-a-server round trip, and its own account wall eventually. iLoveDevTools is the opposite bet: one place, 65 tools, everything processed client-side in your browser tab — nothing you paste is ever transmitted anywhere. No signup, no ads, no server round-trip for your data.

Here's the full list, grouped the same way the site groups them.

PDF Tools

• Merge PDF — Combine multiple PDF files into a single PDF, in whatever order you choose.
• Split PDF — Split a PDF into multiple files at the page numbers you choose, downloaded as a zip.
• Remove PDF Pages — Delete specific pages or page ranges from a PDF.
• Extract PDF Pages — Pull specific pages or page ranges out of a PDF into a new file.
• Organize PDF — Drag to reorder pages, rotate or delete individual pages, all in one visual view.
• Rotate PDF — Rotate specific pages or an entire PDF by 90, 180, or 270 degrees.
• Add Page Numbers — Stamp page numbers onto every page of a PDF, with control over position, format, and starting number.
• Add Watermark — Overlay a text watermark across every page of a PDF, with control over opacity, rotation, and size.
• Crop PDF — Trim margins from every page of a PDF by an exact amount.
• JPG to PDF — Combine JPG or PNG images into a single PDF.
• PDF to JPG — Convert PDF pages into JPG images, individually or as a zip.
• Compare PDF — Compare the text of two PDFs and see exactly what changed.
• OCR PDF — Extract text from scanned or image-based PDFs using on-device OCR.
• PDF to Markdown — Convert a PDF to Markdown with guessed headings and lists.
• Fill PDF Forms — Fill in an existing fillable PDF form and download it.
• Sign PDF — Draw or type a signature and place it anywhere on a PDF page.
• Unlock PDF — Remove protection from a PDF (RC4, AES-128, AES-256) with the password you supply, or none for restrictions-only files.
• HTML to PDF — Convert HTML into a downloadable, paginated PDF.
• Markdown to PDF — Turn Markdown into a paginated PDF with a live preview.
• Protect PDF — Add an AES-256 password to a PDF, with optional print/copy/edit restrictions.
• Compress PDF — Shrink a PDF in your browser, from lossless cleanup to aggressive image recompression.
• Image to PDF — Combine JPG, PNG, WebP, GIF, BMP or AVIF images into one PDF with page size and orientation options.
• PDF to PNG — Render PDF pages to PNG at up to 3x resolution, with a transparent-background option.
• PDF to PowerPoint — Turn a PDF into a .pptx with page images and editable text boxes (approximate layout).
• PDF to Text — Extract the text from a PDF as plain text, with page separators and reflow options.
• PDF Metadata Editor — View and edit a PDF's title, author, subject and keywords, or strip all metadata.
• Flatten PDF — Turn form fields (and optionally annotations) into static page content.
• Word to PDF — Convert a .docx to PDF in your browser (text, headings, lists, tables and images; not exact Word layout).

File Utilities

• PDF to Base64 — Upload a PDF and convert it into a Base64-encoded string for easy sharing or embedding.
• Base64 to PDF — Convert a Base64 string back into a downloadable PDF file.
• Image to Base64 — Turn an image into a data URI or Base64 string, or decode Base64 back into an image.

Encoding & Hashing

• Base64 Encoder — Encode data into Base64, or decode a Base64 string back to its original form.
• URL Encoder — Encode and decode URI components so they're safe to use in URLs.
• Hash Generator — Generate cryptographic hashes (SHA-256, SHA-512) from text.
• UUID Generator — Generate universally unique identifiers with a single click.

Web & API

• JSON Tools — Format, validate, and minify JSON, with automatic fixes for common issues like single quotes and trailing commas.
• JWT Debugger — Decode and inspect a JSON Web Token's header, payload, and signature.
• SQL Formatter — Turn a dense, minified SQL query into consistently indented, readable output.
• cURL Converter — Convert cURL commands into code for JavaScript, Node, Python, PHP, Go, Rust, Java, C#, PowerShell and Ruby.
• JSON to TypeScript — Paste JSON and get TypeScript interfaces or types.

Text & Data

• Regex Tester — Test and debug regular expressions in real time, with syntax highlighting and match results.
• List Utilities — Sort, deduplicate, and count distinct entries in a list.
• Array Generator — Turn a plain list into an array literal for your language of choice.
• Markdown Previewer — Write Markdown and see a live, rendered HTML preview side-by-side.
• Code Diff Viewer — Compare two blocks of text or code and see a visual diff.
• Mock Data Generator — Generate realistic fake data — names, emails, UUIDs, dates, and more — as JSON or CSV.
• Case Converter — Convert text between camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE and more.
• Lorem Ipsum Generator — Generate placeholder paragraphs, sentences or words, optionally wrapped in HTML.
• YAML Formatter — Format, validate and minify YAML with line and column errors.
• XML Formatter — Format, validate and minify XML with line and column errors.
• Word Counter — Count words, characters, sentences and paragraphs, with reading time and top keywords.
• HTML to Markdown — Convert HTML to clean Markdown, or Markdown to HTML with a safe preview.

Converters

• Timestamp Converter — Convert between Unix timestamps and human-readable dates.
• Color Converter — Convert colors between HEX, RGB, and HSL, with a built-in picker.
• Data Format Converter — Convert data between JSON, YAML, and CSV for config files and data exchange.
• CSV to SQL — Convert CSV data into a CREATE TABLE statement and INSERT statements, with column types inferred automatically.
• Cron Expression — Parse a cron expression into a plain-English schedule and see its next upcoming run times.
• Number Base Converter — Convert between binary, octal, decimal, hex and any base from 2 to 36, with two's complement.
• JSON to CSV Converter — Convert JSON to CSV and back, with nested-object flattening and delimiter control.

Image Tools

• Image Resizer — Resize images to exact dimensions or a percentage, in your browser.
• Image Converter — Convert images between PNG, JPG and WebP.
• Image Compressor — Shrink image file sizes without uploading them anywhere.
• SVG Optimizer — Shrink SVG files and export them as PNG.

Why client-side matters

Every tool above runs its transform using your browser's own JavaScript engine — parsing, formatting, hashing, converting. Nothing you paste is uploaded anywhere first. For things like JWTs or config files that can carry real, sensitive data, that's not a minor detail; it's the difference between "this tool happened to not misuse my data" and "this tool architecturally cannot."

That's the whole premise of iLoveDevTools — small, sharp, boring-in-a-good-way utilities, all in one place, none of them capable of seeing what you paste into them.

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