Focal blog https://focaltool.com/blog The Focal team writes about resizing, image formats, caching and page speed. en Mon, 21 Sep 2026 00:00:00 GMT Caching transformed images with Cache-Control, immutable and per-format cache keyshttps://focaltool.com/blog/caching-transformed-imageshttps://focaltool.com/blog/caching-transformed-imagesMon, 21 Sep 2026 00:00:00 GMTCache resized images safely with a long max-age on versioned URLs, immutable for browsers, and a per-format cache key when the format depends on Accept.cachinghttpperformance Crop and fit modes explained, with fill, fit-in and positioned cropshttps://focaltool.com/blog/crop-and-fit-modeshttps://focaltool.com/blog/crop-and-fit-modesMon, 21 Sep 2026 00:00:00 GMTSee how an image service fits a photo into a box, with worked numbers for crop-to-fill, fit-in, full-fit-in, adaptive-fit-in, manual crops and alignment.image-processingecommerce EXIF metadata and privacy, and why GPS data should never reach your usershttps://focaltool.com/blog/exif-metadata-gps-privacyhttps://focaltool.com/blog/exif-metadata-gps-privacyMon, 21 Sep 2026 00:00:00 GMTPhone photos can carry GPS coordinates in their EXIF metadata. Learn what the tags hold, how to check your own images, and how to strip them before delivery.privacyexifsecurity How images affect Largest Contentful Paint, and what to changehttps://focaltool.com/blog/images-largest-contentful-painthttps://focaltool.com/blog/images-largest-contentful-paintMon, 21 Sep 2026 00:00:00 GMTImages are the LCP element on most pages. See where LCP time goes, why image download time is rarely the bottleneck, and which HTML changes load it sooner.core-web-vitalsperformance How images cause Cumulative Layout Shift, and how to reserve their spacehttps://focaltool.com/blog/images-cumulative-layout-shifthttps://focaltool.com/blog/images-cumulative-layout-shiftMon, 21 Sep 2026 00:00:00 GMTImages without dimensions are a top cause of layout shift. See how CLS scores shifts, how width and height reserve space, and how to size art-directed images.core-web-vitalshtmlperformance Resizing images at build time vs on request, and how to choosehttps://focaltool.com/blog/build-time-vs-on-request-image-resizinghttps://focaltool.com/blog/build-time-vs-on-request-image-resizingMon, 21 Sep 2026 00:00:00 GMTCompare resizing images during the build with resizing them on first request, covering build length, file counts, cache misses, new sizes and encoding cost.image-processingarchitectureperformance Responsive images with srcset and sizes, explained with worked exampleshttps://focaltool.com/blog/responsive-images-srcset-sizeshttps://focaltool.com/blog/responsive-images-srcset-sizesMon, 21 Sep 2026 00:00:00 GMTLearn how browsers use srcset width descriptors and the sizes attribute to pick an image file, with worked numbers for a hero banner and a product grid.htmlresponsive-imagesperformance Trimming product photo backgrounds for a consistent catalogue gridhttps://focaltool.com/blog/trim-product-photo-backgroundshttps://focaltool.com/blog/trim-product-photo-backgroundsMon, 21 Sep 2026 00:00:00 GMTProduct photos arrive with uneven white margins. Learn how trim with a colour tolerance, fit-in and fill give every catalogue tile the same framing and scale.ecommerceimage-processing WebP vs AVIF vs JPEG, and which image format to serve in 2026https://focaltool.com/blog/webp-vs-avif-vs-jpeghttps://focaltool.com/blog/webp-vs-avif-vs-jpegMon, 21 Sep 2026 00:00:00 GMTCompare WebP, AVIF and JPEG on file size, encoding cost and browser support in 2026, then serve each one safely with the picture element or the Accept header.image-formatsperformance What an image processing worker is, and how to size concurrency for your traffichttps://focaltool.com/blog/image-processing-workers-concurrencyhttps://focaltool.com/blog/image-processing-workers-concurrencyMon, 21 Sep 2026 00:00:00 GMTAn image worker runs one transformation at a time. Combine your cache hit ratio, peak request rate and processing time with Little's law to size concurrency.image-processingcapacity-planning