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Open-source licenses.

The free in-browser tools on this site are built with vanilla JavaScript plus a handful of excellent open-source libraries. Every one is listed below with its version, license, copyright, and source. All are permissive or LGPL; none restrict use on a commercial site. Each library runs entirely in your browser; nothing you load is ever uploaded.

  • pdf-libv1.17.1 MIT
    © Andrew Dillon and contributors. Create, merge, and modify PDFs in the browser.
    used by: Merge PDFs, Rearrange PDF Pages, JPG to PDF, Watermark PDF
  • pdf.jsv2.16.105 Apache-2.0
    © Mozilla Foundation and contributors. Render PDF pages to canvas for thumbnails and previews.
    used by: Merge PDFs, Rearrange PDF Pages, Watermark PDF, Metadata Viewer
  • modern-gifv2.1.0 MIT
    © wxm. Fast GIF encoder/decoder; used to build animated GIFs from a sequence of images, with palette quantization and dithering.
    used by: Images to GIF
  • fflatev0.8.2 MIT
    © Arjun Barrett. Fast, tiny ZIP/zlib (de)compression; used to unzip Office and OpenDocument files in memory, inflate PNG text chunks, and build the batch download archive in the image converter.
    used by: Metadata Viewer, Images to GIF, Image Converter
  • SortableJSv1.15.2 MIT
    © All contributors to SortableJS. Drag-and-drop reordering of items.
    used by: Merge PDFs, Rearrange PDF Pages, JPG to PDF, Images to GIF
  • qrcode-generatorv1.4.4 MIT
    © Kazuhiko Arase. QR code encoding.
    used by: QR Code Generator, WiFi QR Code, vCard QR Code
  • cronstruev2.50.0 MIT
    © Brady Holt. Translate cron expressions to plain English.
    used by: Cron Expression Builder
  • CSSOv5.0.5 MIT
    © Sergey Kryzhanovsky and contributors. CSS minification.
    used by: CSS Minifier
  • Terserv5.36.0 BSD-2-Clause
    © Mihai Bazon and contributors. JavaScript minification.
    used by: JavaScript Minifier
  • markedv12.0.2 MIT
    © Christopher Jeffrey and contributors. Parse Markdown into HTML.
    used by: Markdown to PDF
  • DOMPurifyv3.0.11 Apache-2.0 / MPL-2.0
    © Cure53 and contributors. Sanitize the HTML produced from Markdown before it's rendered.
    used by: Markdown to PDF
  • highlight.jsv11.9.0 BSD-3-Clause
    © Ivan Sagalaev and contributors. Syntax highlighting for fenced code blocks.
    used by: Markdown to PDF
  • libheif-jsEmscripten port MIT + LGPL-3.0
    libheif-js wrapper © catdad-experiments (MIT). An Emscripten/WASM build of libheif (LGPL-3.0) © Struktur AG / Dirk Farin. Decodes Apple HEIC photos. Loaded as a separate file at runtime (not compiled into our code), so it can be replaced, the LGPL-friendly arrangement.
    used by: HEIC to JPG Converter
  • blueimp-md5 / Joseph Myers MD5 MIT / public domain
    © Sebastian Tschan (blueimp), after Joseph Myers (public domain). A compact MD5 routine adapted into our hash tool (the SHA family uses the browser's native Web Crypto API instead).
    used by: Hash Generator

The permissive license texts are reproduced below. Apache-2.0 and LGPL-3.0 are long and are linked to their canonical copies, which also travel with each library's source above.

MIT License: pdf-lib, SortableJS, qrcode-generator, cronstrue, CSSO, marked, libheif-js wrapper, blueimp-md5

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

BSD 2-Clause License: Terser

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this
   list of conditions and the following disclaimer.

2. Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

BSD 3-Clause License: highlight.js

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this
   list of conditions and the following disclaimer.

2. Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.

3. Neither the name of the copyright holder nor the names of its contributors
   may be used to endorse or promote products derived from this software without
   specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Apache License 2.0: pdf.js, DOMPurify

Licensed under the Apache License, Version 2.0 (the "License"); you may not use
these files except in compliance with the License. You may obtain a copy of the
License at https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed
under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
CONDITIONS OF ANY KIND, either express or implied. See the License for the
specific language governing permissions and limitations under the License.

Full text: https://www.apache.org/licenses/LICENSE-2.0

GNU Lesser General Public License v3.0: libheif

libheif is free software: you can redistribute it and/or modify it under the
terms of the GNU Lesser General Public License as published by the Free Software
Foundation, either version 3 of the License, or (at your option) any later
version. It is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

Full text: https://www.gnu.org/licenses/lgpl-3.0.html

// note
The tools' own source code is © Tiempo Software. Third-party libraries are loaded from their respective CDNs (or, for libheif, self-hosted) in their original, unmodified form; their license banners and notices stay intact. This page is also available as a plain-text THIRD-PARTY-LICENSES.txt.

// acknowledgements
The little arcade in the homepage desktop (Snake, 2048, and Minesweeper) is original, dependency-free code © Tiempo Software, built on long-standing public-domain game mechanics. 2048 was popularized by Gabriele Cirulli (original game MIT-licensed); our implementation shares none of its code, just a tip of the hat to the design. The desktop's 3D Maze and 3D Pipes screensavers are likewise original canvas renderers, fond homages to the classic 1990s Windows screensavers, written from scratch with no code or assets from the originals.

// a free, browser-only toolset by Tiempo Software, built in Omaha, Nebraska. see all tools.