Image optimizer
Resize and encode a JPEG, PNG, or WebP, then compare its actual byte size and download the result.
Run a local test →Reproducible image performance
Make images lighter without guessing.
Use documented tests, copy-ready markup, and browser-only tools to choose formats, responsive widths, and loading behavior for real web pages.
A decision, not a magic score
Dimensionsverify
Qualityinspect
Deliverymeasure
Every guide separates confirmed standards, repeatable test steps, and context-dependent judgment.
Local by default
Tool uploads stay in your browser. The server does not receive your source image.
Conditions shown
Useful results name the file, viewport, browser, cache state, and test date.
Primary sources
Claims link to browser, web standards, Google, or WordPress documentation.
Start here
Two working tools
Run a comparison on your own file or generate responsive-image markup without sending data to us.
Srcset builder
Create a width-descriptor candidate list and a transparent transfer-size estimate from your declared inputs.
Build markup →Testing record
Use the same environment fields each time so another reader can understand and repeat the test.
Read the method →Latest field guides
Practical, source-backed notes
Evaluate a WordPress Image Optimization Plugin Without Marketing Claims
A reversible checklist for testing an image plugin’s output, markup, privacy, compatibility, cost, and rollback path.
Open guide →Audit WordPress Image Sizes Before Adding an Optimization Plugin
Inventory registered sizes, generated files, template slots, and currentSrc choices before installing another image plugin.
Open guide →A Safe WordPress Image Upload Workflow From Master to Published Page
Keep archival masters separate, create intentional derivatives, write contextual alt text, and verify what WordPress actually serves.
Open guide →Audit Every Image Request With Chrome DevTools
A request-by-request image audit that records bytes, dimensions, initiators, priority, cache behavior, and page context.
Open guide →Test decoding=”async” Without Guessing at Rendering Impact
Understand the decoding hint, design a controlled visual test, and document when async decoding helps or changes presentation.
Open guide →Use fetchpriority and Preload for an LCP Image—Then Measure
Separate discovery from priority, test a likely LCP image, and avoid piling hints onto every above-the-fold asset.
Open guide →