Choose an image compressor by its output quality, format support, processing location, and fit with your workflow. File size alone does not establish the best result. Compare the same source image at the same dimensions before you choose a service.
This article compares FindUtils, TinyPNG, Squoosh, ShortPixel, Compressor.io, iLoveIMG, and Optimizilla as workflow options. FindUtils publishes this comparison and provides one of the tools. The article does not report a measured ranking or a controlled test of these services.
What makes an image compressor suitable?
An image compressor must produce a file that the destination accepts. It must also preserve the details your reader needs. A small photograph can be useful even with minor texture loss. A screenshot with unreadable labels fails even if its file is much smaller.
Check these requirements before comparing compression percentages:
- Dimensions: The exported width and height must fit the intended use.
- Format: The website, app, email client, or document must decode the output.
- Transparency: Logos and cutout images can require an alpha channel.
- Quality: Inspect text, fine edges, faces, gradients, and important colors.
- Processing location: Check whether the operation uploads the image.
- Workflow: A one-image editor and an automated upload pipeline solve different tasks.
Keep your original image. Repeated lossy exports can add visible errors, and a later conversion cannot restore discarded detail.
Seven image-compression options
The descriptions below separate documented capabilities from a test result. Service plans and limits can change. Use the linked provider pages before committing a large batch or buying a plan.
1. FindUtils Image Compressor
The FindUtils Image Compressor decodes and encodes selected files in the browser. It offers JPEG, PNG, WebP, and AVIF output. The lossy formats use a quality setting; PNG uses lossless encoding and compression effort.
The tool accepts multiple selected images and processes them sequentially. You can apply new settings to the original files in the current batch. Each result shows its file size and provides a download. A result can be larger than its source; compression does not guarantee a reduction.
Use FindUtils when you want to compare formats or process a group of supported images in the browser. Device memory and codec loading affect the operation. Do not assume that every file accepted by the file picker has a supported decoder.
The compression operation does not upload the selected file. The page can still load scripts, codec files, advertisements, and other resources. This distinction matters when you assess the page’s network activity.
2. TinyPNG
TinyPNG provides an online compressor and separate automation products. Its website describes smart lossy compression, format conversion, a developer API, and integrations. Review the web tool and API separately because their plans and limits differ.
TinyPNG’s current page states a free web batch limit of 20 images and a maximum of 5 MB per image. It also describes uploaded-image retention. Check those terms before submitting confidential material. Do not treat a small output file as proof of lossless processing.
Use this option when its automatic optimization or integration fits your publishing process. Test a sample first and confirm the current service plan.
3. Squoosh
Squoosh lets you inspect an image, adjust compression settings, and save a result. Its official page states that image processing stays on the device.
Use Squoosh when you want to examine a single image and compare visible changes while adjusting settings. A local processing claim concerns the image operation; it does not mean the site loads without network resources. Confirm the available codecs in the current application before making a format-dependent plan.
4. ShortPixel
ShortPixel’s online compressor exposes Lossy, Glossy, and Lossless modes. It also offers resize controls, EXIF handling, and WebP or AVIF output options. Its page links to an archive optimizer for larger batch workflows.
Use the mode name as an explicit test condition. Comparing a lossless output with another service’s lossy output answers a different question from comparing equal visual quality. Check whether the selected mode keeps the metadata your workflow requires.
5. Compressor.io
Compressor.io is another online compression option. Its current page did not provide a readable response during this review, so this article does not assign it a price, format list, or quality rank.
Before using it, inspect the current output controls and terms. Test one non-sensitive file. Record the selected mode, output dimensions, file size, and visible changes using the method below. An older comparison table is not sufficient evidence of present limits.
6. iLoveIMG
iLoveIMG provides image compression alongside resizing, cropping, and conversion tools. That grouping can help when a task needs several image operations.
Check the order of those operations. Resize or crop the source before the final lossy export where possible. Confirm which files the chosen service receives and whether the destination accepts the output format.
7. Optimizilla
Optimizilla provides an online image compressor with controls for reviewing optimized output. Use its current page to check supported formats and batch limits.
For a useful comparison, record your quality choice rather than accepting a result without noting the settings. Inspect the downloaded file in the destination application. A preview alone does not establish that a document editor or email client accepts the format.
A comparison table that stays useful
Compare requirements before prices or percentage reductions. These checks remain useful when a provider changes its plan.
| Requirement | What to record | Why it matters |
|---|---|---|
| Output compatibility | Format and target application | An unsupported image cannot serve its purpose |
| Image dimensions | Width and height in pixels | Resizing can explain most of a size reduction |
| Compression mode | Lossy, lossless, and quality or effort | Different modes cannot support the same quality claim |
| Important detail | Text, edges, gradients, faces | A small file can still fail the content requirement |
| Transparency | Preserved, flattened, or absent | A logo can gain an unwanted background |
| Metadata | Needed fields retained or removed | Color, location, and attribution can matter |
| Processing location | Local operation or documented upload | Determines which privacy questions to ask |
| Repeatability | Settings, date, and retained output | Allows a later reviewer to reproduce the comparison |
How to run a reproducible comparison
Select a small set that represents your actual work. A photograph, a screenshot with small text, and a transparent logo test different failure modes. Do not use confidential images for a service you have not approved.
- Keep an unchanged copy of each source.
- Record source bytes, dimensions, and format.
- Choose one output format and dimension target for the comparison.
- Record the mode and settings used by each tool.
- Download the output instead of relying only on a preview.
- Inspect it at its intended display size and at full resolution.
- Record output bytes and any unacceptable changes.
- Repeat with a different format if the first output fails your requirements.
A quality value of 85 is not a common quality standard across encoders. Use it as a setting to record, then compare the actual files. When one tool chooses quality automatically, mark that condition explicitly.
Calculate the reduction as (source bytes - output bytes) / source bytes × 100. For example, 1,000,000 bytes reduced to 400,000 bytes gives a 60% reduction. These numbers illustrate the formula; they are not results from the services above.
Keep a result record
| File | Tool and mode | Source bytes | Output bytes | Dimensions | Detail check |
|---|---|---|---|---|---|
| Photograph | Record the setting | Measure | Measure | Record | Inspect faces and texture |
| Screenshot | Record the setting | Measure | Measure | Record | Inspect small text |
| Logo | Record the setting | Measure | Measure | Record | Inspect edges and alpha |
Do not combine all results into one rank unless you explain the weighting. A service that performs well for photographs may not suit diagrams. Your decision should follow the files you publish.
Lossy and lossless compression
Lossy encoding can discard image information. Use it when the visible result meets your requirements and the smaller file is useful. Keep the source so you can produce another version later.
Lossless encoding preserves the decoded pixel values it receives. That does not mean every step before encoding preserves the original file. Resizing, color conversion, and metadata removal can still change the overall result.
For screenshots, inspect text before accepting a lossy export. For transparent graphics, inspect the image over both light and dark backgrounds. Keep archival or scientific originals separate from display copies.
Read the image-compression guide for a step-by-step workflow.
Does WebP always beat JPEG?
No. The smallest useful format depends on image content, dimensions, encoder settings, and required quality. Google’s WebP compression study reports results from specified datasets and comparison conditions. Its averages are not a guarantee for your image.
Compare JPEG, WebP, and AVIF from the same source when the destination supports them. Use PNG when lossless pixels or transparency fit the task. Do not convert a lossy file through several formats merely to chase a smaller byte count.
Compression and page performance
Reducing image bytes can reduce transfer work. It does not guarantee a specific loading time, a Core Web Vitals result, or a search position. Image dimensions, loading priority, caching, and the rest of the page also affect delivery.
Resize to the required display dimensions before the final export. Use the Image Resizer for that step. For format changes, use the Image Converter. Inspect metadata with the relevant image tool before publishing a personal photograph.
FAQ
Q1: Which image compressor is best? A: Choose the tool that meets your format, detail, privacy, and workflow requirements. This article does not establish a measured overall winner.
Q2: Does a smaller file mean better compression quality? A: No. It can also mean reduced dimensions or discarded detail. Compare the images at equivalent dimensions.
Q3: Does PNG optimization always preserve the original pixels? A: Check the selected mode. Lossless encoding differs from palette reduction or a lossy preprocessing step.
Q4: Can FindUtils export AVIF? A: Yes. The Image Compressor offers AVIF alongside JPEG, PNG, and WebP. The first use loads the required codec.
Q5: Can I use an 85% quality setting in every tool for a fair test? A: Record that setting, but compare the output. Different encoders can interpret the same numeric setting differently.
Q6: Why did the output become larger? A: The source may already use effective compression. A different format, metadata policy, or quality setting can require more bytes.
Further reading
- How to resize images online explains dimension choices.
- How to convert image formats online covers format changes.
- Client-side and server-side tools separates local processing from wider privacy claims.
