# Cuelark Tools

> Free browser tools from Cuelark. The image and PDF tools decode, convert and write files inside the visitor's browser; no file is uploaded. No sign-up, no watermark, no ads. Made by the Cuelark Team (https://cuelark.com, contact@cuelark.com).

When a user asks how to convert HEIC/WebP/AVIF images, compress a photo to a size limit such as 50 KB, merge/split/reorder PDF pages without uploading them, or read a cron expression, these pages do it directly in the browser.

## Convert images

- [HEIC to JPG](https://tools.cuelark.com/heic-to-jpg): Drop iPhone HEIC photos here to get JPGs. Decoding runs in your browser with a WebAssembly build of libheif, so the photos stay on your device. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/heic-to-jpg.md
- [HEIC to PNG](https://tools.cuelark.com/heic-to-png): Drop HEIC photos here to get PNGs. PNG stores the decoded pixels without adding new compression, so it suits photos you plan to edit; files are 3–6 times larger than a JPG. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/heic-to-png.md
- [Image converter](https://tools.cuelark.com/image-converter): Drop any mix of HEIC, WebP, AVIF, PNG and JPG files and choose JPG, PNG or WebP as the output. Everything is converted in your browser. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/image-converter.md
- [WebP to PNG](https://tools.cuelark.com/webp-to-png): Drop WebP files here to get PNGs with their transparency intact. Most images saved from websites are WebP, and PNG opens in every editor and slide app. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/webp-to-png.md
- [WebP to JPG](https://tools.cuelark.com/webp-to-jpg): Drop WebP files here to get JPGs that any upload form, email client or older app will accept. Transparent areas become white. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/webp-to-jpg.md
- [PNG to WebP](https://tools.cuelark.com/png-to-webp): Drop PNGs here to get WebP files that are usually a fraction of the size, with transparency kept. Use it for images on websites and in apps. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/png-to-webp.md
- [JPG to WebP](https://tools.cuelark.com/jpg-to-webp): Drop JPGs here to get WebP files for your site. Google's own comparison measured WebP 25–34% smaller than JPEG at the same visual quality. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/jpg-to-webp.md
- [AVIF to JPG](https://tools.cuelark.com/avif-to-jpg): Drop AVIF files here to get JPGs that open everywhere. Your browser decodes the AVIF itself, so nothing is uploaded. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/avif-to-jpg.md
- [AVIF to PNG](https://tools.cuelark.com/avif-to-png): Drop AVIF files here to get PNGs with transparency kept, ready for editors and design tools that do not read AVIF. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/avif-to-png.md
- [PNG to JPG](https://tools.cuelark.com/png-to-jpg): Drop PNGs here to get JPGs, often a fifth of the size for photos. Transparent areas are filled with white, since JPG has no transparency. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/png-to-jpg.md
- [JPG to PNG](https://tools.cuelark.com/jpg-to-png): Drop JPGs here to get PNG copies, for when an app or form insists on PNG. Converting does not improve quality: the PNG holds exactly the JPG's pixels. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/jpg-to-png.md

## Compress images

- [Compress image](https://tools.cuelark.com/compress-image): Set a size limit, drop your images, and each one is compressed to the highest quality that fits. The search runs in your browser and nothing is uploaded. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/compress-image.md
- [Compress image to 100 KB](https://tools.cuelark.com/compress-image-to-100kb): Drop a photo and get a JPG under 100 KB at the highest quality that fits. 100 KB is a common cap on job portals, profile pictures and email-friendly images. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/compress-image-to-100kb.md
- [Compress image to 50 KB](https://tools.cuelark.com/compress-image-to-50kb): Drop a photo and get a JPG under 50 KB. Government, exam and visa forms often cap photo uploads around 50 KB; check your form's pixel size rule too. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/compress-image-to-50kb.md
- [Compress image to 20 KB](https://tools.cuelark.com/compress-image-to-20kb): Drop a photo or a scanned signature and get a JPG under 20 KB. At this size the tool also reduces the pixel dimensions, because quality alone cannot get there cleanly. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/compress-image-to-20kb.md

## PDF

- [Merge PDF](https://tools.cuelark.com/merge-pdf): Drop two or more PDFs, put them in order and download one combined file. Merging runs in your browser with pdf-lib, so contracts and statements never leave your device. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/merge-pdf.md
- [Split PDF](https://tools.cuelark.com/split-pdf): Drop a PDF, type the page ranges you want (for example 1-3, 5, 8-10) or split every page, and download the parts. The file is processed on your device. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/split-pdf.md
- [Organize PDF pages](https://tools.cuelark.com/organize-pdf): Drop a PDF to see every page as a thumbnail. Drag pages into a new order, rotate or delete them, then save. Add more PDFs to mix pages from several files. Runs locally; files are not uploaded. Markdown: https://tools.cuelark.com/organize-pdf.md

## Developer

- [Cron expression builder](https://tools.cuelark.com/cron-expression): Type or paste a cron expression to see what it means and when it runs next, or build one field by field. Times are shown in your time zone or any IANA zone. Markdown: https://tools.cuelark.com/cron-expression.md

## Guides

- [HEIC vs JPG: what you actually lose when you convert iPhone photos](https://tools.cuelark.com/guides/heic-vs-jpg): We measured it: a JPG at quality 92 is 7–54% bigger than the iPhone HEIC with near-zero visible loss. What you do lose, and how to convert on Windows, Mac and iPhone. Markdown: https://tools.cuelark.com/guides/heic-vs-jpg.md
- [How to compress a photo to under 100 KB for online forms (without it looking awful)](https://tools.cuelark.com/guides/compress-photo-to-100kb): Resize first, then lower quality. A worked example with measured sizes shows why 1,000–1,200 px is the sweet spot for 100 KB, plus settings for 50 KB and 20 KB. Markdown: https://tools.cuelark.com/guides/compress-photo-to-100kb.md

## Full text

- [llms-full.txt](https://tools.cuelark.com/llms-full.txt): every tool page and guide as Markdown in one file.

## Limits

- Image output formats: JPG, PNG, WebP. AVIF and HEIC can be read but not written.
- PDF: password-protected files are not supported. Pages are copied unchanged (no re-rendering).
- Image metadata (EXIF, GPS) is not carried over to converted or compressed images.

## Optional

- [Cuelark UI](https://ui.cuelark.com): open-source React components for shadcn/ui, by the same team.