If a photo exceeds an upload limit or compressed slide text becomes unreadable, start with accepted format, byte limit and required dimensions.
The image compressor starts processing when you select files, using the current settings. Keep your originals. The dimensions and byte examples below are calculations, not measured compression results for a particular photo.
Choose the next action from the problem
| Problem | First check | Next action |
|---|---|---|
| Photo exceeds an attachment limit | Byte limit and accepted formats | Resize to the needed dimensions, then adjust quality gradually |
| Text or equations become blurry | Compare text at actual size | Consider PNG and retain enough pixels |
| Transparent background is required | Output supports alpha | Use PNG / WebP and inspect edges |
| Destination accepts only JPEG | Actual source format | Use the image converter, then check size |
| A web page loads slowly | Whether the image is the bottleneck | Measure dimensions, transferred bytes and loading behavior |
| Print looks blurry | Print dimensions and required pixels | Preserve required resolution before compression |
Quality, dimensions and format are different controls
Quality 0.7 does not mean the file will be 70% of its original size. Results depend on content, format and browser encoding. An already small image may not become smaller.
| Format | Main properties | Check before choosing |
|---|---|---|
| JPEG | Lossy photographic compression | No transparency; inspect text and edges |
| PNG | Lossless encoding and transparency | Its settings do not behave like JPEG quality; resizing still changes pixels |
| WebP | Supports lossy/lossless and alpha | This tool has no explicit lossless-mode selector; check destination support |
See MDN’s format guide. A PNG output does not promise identical file bytes, metadata or colors after processing.
This compressor has no output-format selector. JPEG, PNG and WebP inputs generally retain their input format. Use the format conversion guide when you need another format. Do not use this workflow where animation or multiple frames must be retained.
Maximum width actually limits the longer edge
The field is passed to the library as maxWidthOrHeight, preserving aspect ratio.
| Original dimensions | Long-edge cap | Example resized dimensions |
|---|---|---|
| 4800 × 3200 px landscape | 1920 px | 1920 × 1280 px |
| 3200 × 4800 px portrait | 1920 px | 1280 × 1920 px |
| 1200 × 800 px | 1920 px | No enlargement from this cap |
Large inputs can be reduced further by browser canvas limits or the library’s size target. See the library documentation: a setting does not guarantee an exact output size or dimension in every environment.
A 2 MB limit is not the same as 2 MiB
NIST’s binary-prefix reference distinguishes decimal and binary units.
| Unit or limit | Bytes |
|---|---|
| 1 kB | 1,000 B |
| 1 KiB | 1,024 B |
| 2 MB | 2,000,000 B |
| 2 MiB | 2,097,152 B |
This site’s displayed sizes use 1024-based conversion with KB / MB labels. A displayed rounded value may not match the destination’s limit. Check the downloaded file’s actual byte count; the byte converter can help compare units.
Compress and download without losing necessary detail
- Retain the original and check the destination’s format, size limit and required dimensions. Quality 0.7 can be a starting trial for photos; start higher for text-heavy images and compare.
- Set quality and Maximum width before selecting JPEG, PNG or WebP files in the compressor. Multiple files are supported. Changing settings afterward does not recompute existing results.
- Compare before/after sizes and previews. Download and inspect text, faces, edges and transparency at actual size. If needed, change settings and select the original files again.
The per-file input limit is 50 MiB (52,428,800 bytes). Large pixel dimensions and multiple files can consume substantial memory even below that byte limit. Reduce the batch or use the image resizer first if processing fails.
Set options, then choose the original
Compare quality, long-edge size and output bytes
Processing runs in the browser. Keep the original and inspect the downloaded file.
Measure web performance and search outcomes separately
Google’s page-experience guidance does not promise high rankings from good Core Web Vitals alone. If an image is the LCP element, optimization can be relevant, but fewer bytes alone do not prove more search visits or fewer exits.
Measure the same page before and after, then compare Search Console’s performance and Core Web Vitals data when enough observations exist. Treat outcomes as unmeasured when data is insufficient.
Frequently asked questions
Can it guarantee a file below 200 KB?
No. There is no user-selectable exact byte target. Test whether the required dimensions and visual quality fit the limit; check alternative submission methods if they do not.
Can I restore the original quality?
Raising quality later cannot recover information lost through downscaling or lossy compression. Reprocess the original rather than an earlier compressed copy.
How can I repeat the workflow next time?
Favorite the tool on the same browser and note starting quality and long-edge values for each purpose. Favorites save the tool’s entry point, not images or compression settings.
Verification scope
On 24 October 2026, the library documentation was compared with the tool’s options, input limit and reprocessing behavior. Matching JPEG, PNG and WebP output types and download extensions is included in verification. The dimension table contains calculated examples. Compression ratios, print suitability, animation retention and ranking improvements are not measured or guaranteed here.
