A clear processing boundary
Local uploads never need the network path. URL modes use constrained fetching only because browsers cannot always read remote resources directly.
A TinyPNG Alternative for Local and URL Workflows
Compare CompressByURL and TinyPNG for local privacy, supported formats, batch limits and URL-based image workflows.
Local processingBatch readyIndividual or ZIP download
Settings
Upload and compress images
Drop or paste images here
JPEG, PNG, WebP or static AVIF. Add one file or a whole batch.
- JPEG
- PNG
- WebP
- AVIF
Local files never leave your device.
Choose by workflow, not mascot or marketing claim.
Use the working compressor below, then compare the workflows on verifiable boundaries: where local files are processed, which formats are supported, and whether your job begins with files, one image URL or a webpage URL.
- Best fit
- Local files plus direct image and webpage URLs
- Processing
- Local for files; bounded fetch for URL modes
- Review date
- September 14, 2026
Different scope, stated plainly
TinyPNG supports additional formats and its own analyzer. CompressByURL concentrates on four static formats and one connected file, image-URL and webpage workflow.
Evidence review · September 14, 2026
CompressByURL vs TinyPNG
The practical difference is the processing boundary and workflow, not a promise that one encoder always makes smaller files. TinyPNG also has a separate website analyzer, so webpage scanning is not presented here as exclusive.
| Workflow | CompressByURL | TinyPNG |
|---|---|---|
| Local-file privacy | Files chosen from your device are decoded and encoded locally in the browser. | The official FAQ says uploaded images are retained for no more than 48 hours. |
| Batch workflow | The browser queue accepts multiple supported files and can package successful results as a ZIP. | The free web tool currently says 20 images up to 5 MB each; conversion is limited to three images. |
| Format scope | JPEG/JPG, PNG, WebP and static AVIF are supported; animated formats are intentionally excluded. | The web tool lists JXL, AVIF, WebP, JPEG/JPG, PNG and APNG support. |
| URL workflows | One direct public image URL or one public webpage can feed the local optimization workflow. | Tinify advertises a separate Website Image Analyzer and separate Developer API. |
Sources reviewed: TinyPNG compressor and FAQ, TinyPNG Website Image Analyzer, Tinify Developer API. Features and limits can change; verify the linked product before making a decision.
How it works
This comparison does not claim that one encoder always wins. Test representative images, inspect the output, and keep the original whenever a result is larger or visually unsuitable.
Start with local files
Add JPEG, PNG, WebP or static AVIF files. The browser validates and previews them without sending local bytes to the server.
Set the outcome
Choose Smart, manual quality, resize, output format or an explicit target-size ceiling.
Use URLs when needed
For remote work, switch to Image URL or Website URL; fetched image bytes join the same local compression queue.
Useful for
- Keep local upload bytes on your device during compression.
- Compress one public image without downloading it manually first.
- Scan a public webpage and optimize selected candidates locally.
Questions about a tinypng alternative for local and url workflows
Is CompressByURL always better than TinyPNG?
TinyPNG is a polished choice for straightforward upload compression and supports formats beyond CompressByURL's static four-format scope. Choose based on the workflow and formats you actually need, not a universal quality claim.
Are all CompressByURL modes completely offline?
No. Files selected from your device remain in your browser, but Image URL and Website URL modes need a bounded network fetch to obtain the public resource you request. Compression still runs locally afterward.
Does TinyPNG have a website image scanner?
TinyPNG currently advertises a separate Website Image Analyzer. CompressByURL connects its single-page discovery results directly to selection, local optimization and replacement-bundle workflows.