Instantly check any image's resolution, real DPI/PPI, print size, dominant colors, EXIF metadata, quality score and social-media fit — all offline, nothing uploaded.
JPG · PNG · WebP · GIF · BMP · SVG · AVIF · ICO — up to several at once
Every digital image is a grid of tiny coloured squares called pixels. Image resolution is simply how many of those pixels an image contains, written as its width multiplied by its height — for example 1920×1080. The more pixels an image has, the more fine detail it can hold, and the larger it can be printed or displayed before those individual squares become visible to the eye. Understanding resolution, and its close cousins DPI and PPI, is the single most useful skill for anyone who works with photos, designs for print, publishes on the web, or posts on social media. This guide explains all of it in plain language, and the checker above puts every one of these numbers at your fingertips instantly and privately.
Resolution is the pixel count of an image. A photo that is 4000 pixels wide and 3000 pixels tall has a resolution of 4000×3000, which is twelve million pixels, or 12 megapixels. Resolution alone does not have a physical size — a 4000×3000 image can be shown as a tiny thumbnail or blown up onto a billboard. What changes is how densely those pixels are packed into the physical space, and that is where DPI and PPI come in. When people ask "what resolution is my image," they almost always want two things: the pixel dimensions (width × height) and a sense of whether that is enough pixels for their intended use. The checker answers both: it shows the exact dimensions, the total pixel count, the megapixels, the aspect ratio, and the orientation, then goes further and tells you how large the image can be printed cleanly and how it fits common screen and social sizes.
DPI stands for dots per inch. It is a printing term that describes how many individual dots of ink a printer lays down within one inch of paper. A higher DPI means the dots are smaller and closer together, producing smoother gradients and finer detail. The industry standard for high-quality photographic printing is 300 DPI: at that density the human eye, at normal viewing distance, cannot pick out individual dots, so the print looks continuous and sharp. Newspapers historically printed at 85–150 DPI, glossy magazines at 300 DPI, and fine-art giclée prints sometimes at 600 DPI or more. DPI only becomes meaningful when an image is printed; on a screen, the equivalent concept is PPI.
PPI stands for pixels per inch and describes pixel density — how many pixels fit into one inch of a digital image or a physical display. Your phone screen might be 460 PPI, a laptop 130–220 PPI, and an older desktop monitor around 96 PPI. PPI is a property of the file or the screen, whereas DPI is a property of the printed output. When you set an image to "print at 300 DPI," you are really telling the printer to place your pixels at a density of 300 pixels per inch, so PPI in the file becomes DPI on the paper. Because of this direct relationship, the two terms are used interchangeably in everyday speech, and this tool reports both.
The clearest way to remember the distinction is this: PPI is about pixels in a file or on a screen; DPI is about ink dots on printed paper. A digital photo has PPI; a printed photo has DPI. Confusion arises because image editors label the same metadata field "DPI" even though it is technically PPI, and because raising the "DPI" number in a file does not create new detail — it only changes the intended print size. If you take a 600×600 pixel image and change its DPI tag from 72 to 300, you have not added a single pixel; you have simply told the printer to squeeze the same 600 pixels into a smaller two-inch square. Real quality comes from having enough pixels in the first place, which is why this checker focuses on the true pixel dimensions and clearly labels any DPI value it has to estimate.
Think of an image as a mosaic. Each tile is one pixel of a single colour. From a distance the mosaic looks like a smooth photograph; up close you see the tiles. Resolution determines how many tiles you have to work with. If you print or zoom an image larger than its pixels allow, the browser or printer has to guess the colours in between existing pixels — a process called interpolation or upscaling — and the result looks soft or blocky. This is why a small web image cannot simply be "made high resolution" by resizing it up: the missing detail was never captured. Conversely, an image with more pixels than the display needs is downscaled, which looks great but wastes bandwidth. The art of working with images is matching the pixel count to the job: plenty of pixels for print and cropping, just enough for the web.
For sharp prints, target 300 DPI. To find the pixels you need, multiply the print size in inches by 300. A 4×6 inch photo needs 1200×1800 pixels; an 8×10 needs 2400×3000; an A4 sheet (8.27×11.69 in) needs about 2480×3508. Posters and banners viewed from a distance are more forgiving — 150 to 200 DPI is usually indistinguishable from 300 DPI when the viewer stands a metre or more away, which is why a large trade-show banner does not need tens of thousands of pixels. The checker's print-size table shows exactly how big your image prints at 72, 96, 150, 200, 300 and 600 DPI in inches, centimetres and millimetres, so you never have to do the maths yourself.
Screens render at roughly 72–96 PPI in CSS terms, but modern "retina" displays pack two or three physical pixels into each CSS pixel. The practical rule for the web is to export images at the pixel size they will be displayed, or up to twice that for retina sharpness, and then compress them. A full-width hero banner might be 1600–1920 pixels wide; a blog thumbnail 400–600 pixels; a product photo 800–1200 pixels. Oversized images are the most common cause of slow pages, so once you know the resolution from this tool, pair it with an image compressor and a modern format like WebP or AVIF to keep files small and Core Web Vitals green.
Each platform crops and compresses to its own specification, so uploading the correct size preserves quality and avoids awkward cropping. Instagram square posts are 1080×1080, portrait posts 1080×1350, and stories and reels 1080×1920. Facebook shared posts look best around 1200×630, and a Facebook cover is 820×312. A Twitter/X header is 1500×500, a LinkedIn banner 1584×396, and a Pinterest pin 1000×1500. The social-media fit panel in this tool compares your image against all of these and labels each as a perfect fit, needing a resize, too small or too large, so you can post with confidence.
A YouTube thumbnail should be 1280×720 (16:9) and under 2 MB, because a crisp, correctly sized thumbnail directly affects click-through rate. A YouTube channel banner is 2560×1440, with the important content kept within a central 1546×423 "safe area" that shows on every device. Video itself is delivered at 1280×720 (HD), 1920×1080 (Full HD) or 3840×2160 (4K). Using the right pixel dimensions means YouTube's own compression has less work to do, so your thumbnail and banner stay sharp.
Instagram's sweet spot is a 1080-pixel width. Feed squares are 1080×1080 (1:1), portraits 1080×1350 (4:5, which takes up the most feed space), landscapes 1080×566 (1.91:1), and stories and reels 1080×1920 (9:16). Upload larger than 1080 wide and Instagram simply downscales it, sometimes with heavier compression, so matching 1080 keeps your images crisp. The checker flags whether your image already matches these targets.
Most passport photos are 2×2 inches at 300 DPI, which is 600×600 pixels; UK-style photos are 35×45 mm. Because official photos are printed and scanned, they demand a true 300 DPI or higher and an exact aspect ratio — this is one of the few web uses where DPI genuinely matters. The tool tells you both the pixel size and whether your image meets the density a passport office expects.
Large-format printing scales resolution to viewing distance. A poster meant to be read from arm's length (an A3 at 300 DPI needs roughly 3508×4961 pixels) demands full resolution, while a highway billboard viewed from dozens of metres can be produced at 20–50 DPI and still look perfect. The key number is the effective DPI at the final printed size, which the checker calculates for you so you never send a file that will look pixelated on the wall.
Knowing an image's true resolution lets you predict print quality before you pay for printing, avoid uploading files that are too small for a job, keep web pages fast, hit exact social-media specifications, and communicate precisely with printers, clients and designers. It turns guesswork into confident decisions.
Resolution is only one dimension of quality. A high-resolution image can still be blurry, noisy, badly exposed or heavily compressed. That is why this tool also estimates sharpness, contrast, brightness and compression quality, and combines them into a quality score — because pixel count alone never tells the whole story. Browsers also cannot decode every format (TIFF and HEIC often fail), and DPI metadata is frequently missing, in which case the tool estimates and says so.
Photographers verify that a client file is large enough for the requested print. Designers confirm a logo has the density for business cards. E-commerce sellers ensure product photos meet a marketplace's minimum pixels. Bloggers and SEOs keep images light for fast, Google-friendly pages. Students and job seekers size passport and ID photos correctly. Social media managers post at exact platform dimensions. Print shops screen incoming files before running a job. In every case, a few seconds with this checker prevents an expensive or embarrassing mistake.
When you drop an image into the checker, start with the pixel dimensions — they are the ground truth. Next look at the effective DPI at your target print size: if it drops below about 200, the print will start to soften. Then read the quality score, which blends sharpness, contrast and compression; a high-resolution but low-scoring image usually means heavy compression or focus problems at the source. Finally, use the social and print-readiness panels to match the file to its destination. With practice, these numbers become second nature, and you will instinctively know whether any image is right for the job — but the tool will always confirm it in a second, entirely on your own device.
Checking resolution has never been simpler. Drag an image onto the drop zone above, click to browse your files, or simply copy any picture and press Ctrl+V to paste it directly. The moment the file is read, the tool decodes it locally and displays the width and height in pixels, the total pixel count, the megapixels and the aspect ratio. You do not install anything, create an account, or wait for an upload — because there is no upload. Everything is computed on your own machine using the browser's built-in image engine, which is why it is both instant and completely private. You can load several images at once and switch between them using the thumbnail strip, and you can zoom the preview or open it fullscreen to inspect fine detail. When you are done, one click exports a full report or copies the numbers to your clipboard, so the information flows straight into your emails, specs and design notes.
The format an image is saved in has a large effect on file size, quality and where it can be used. JPEG (JPG) is the universal choice for photographs; it uses lossy compression to make small files, at the cost of some detail, and it supports EXIF metadata. PNG is lossless and supports transparency, which makes it perfect for logos, icons and screenshots, but produces much larger files for photographs. WebP and AVIF are modern formats that deliver JPEG-beating quality at a fraction of the size and are the best choice for fast websites. GIF is limited to 256 colours and is used mainly for simple animations. SVG is a vector format that scales to any size without losing sharpness, ideal for logos and icons. BMP and TIFF are older, very large formats used in some professional and archival workflows, and HEIC is Apple's efficient photo format that many browsers still cannot decode. When a browser cannot decode a format such as HEIC or TIFF, this checker tells you clearly rather than showing wrong numbers, and it still reports the file's basic details.
Beyond pixel count, three quieter properties shape how an image looks. Colour space defines the range of colours a file can describe; sRGB is the safe standard for the web and most screens, while wider spaces like Adobe RGB or Display P3 hold richer colours for professional print and modern displays. Bit depth is how many shades each colour channel can take: 8-bit gives 256 levels per channel (16.7 million colours), while 10-bit or 16-bit files hold far more, which prevents banding in smooth gradients like skies. Dynamic range is the spread between the darkest and brightest tones an image preserves; a wide dynamic range keeps detail in both deep shadows and bright highlights, which is why a well-exposed photo looks natural while a clipped one loses information that can never be recovered. The checker reads colour space from EXIF where available and estimates brightness, contrast and tonal spread from the pixels themselves.
Two images with identical pixel dimensions can look completely different because of compression. Every time a JPEG is saved, a little detail is discarded to shrink the file; save it repeatedly and the losses accumulate into blocky artefacts and fuzzy edges — a problem known as generation loss. The tool estimates compression quality from the number of bits stored per pixel: a heavily compressed file carries very few bits per pixel and often looks soft, while a lightly compressed or lossless file carries many. This is why the quality score can be low even for a large, high-megapixel image, and why simply enlarging a compressed photo makes things worse rather than better. For the best results, always keep and edit a high-quality master, and export a fresh compressed copy for each destination rather than re-saving the same JPEG over and over.
Modern phones, tablets and laptops pack two, three or even four physical pixels into every CSS pixel, which is why text and images look razor sharp on them. For designers this means a button that occupies 100 CSS pixels may need a 200- or 300-pixel image to stay crisp on a retina screen. The practical rule is to export web images at roughly twice their displayed size for high-DPI sharpness, then compress aggressively so the extra pixels do not slow the page. Understanding device pixel ratio explains why an image that looks perfect on an old monitor can appear slightly soft on a new phone, and why "resolution" on the web is always a balance between sharpness and speed.
Photographs taken with a phone or camera usually carry EXIF metadata: the camera and lens model, ISO, shutter speed, aperture, focal length, the date and time the photo was taken, and often the exact GPS coordinates. This information is invaluable for photographers reviewing their settings, but it is a privacy risk when images are posted publicly, because it can reveal where and when a photo was taken. This checker reads and displays all of that metadata locally so you can see exactly what a file is carrying before you share it. If you want to remove it, the companion EXIF Viewer & Remover tool strips the data cleanly. Screenshots, web graphics and most PNGs contain no EXIF at all, which is why the tool will honestly report "no EXIF data found" for them instead of inventing values.
If a print came back blurry, check whether the effective DPI at that size dropped below about 200 and whether the quality score flagged softness or heavy compression. If a social post looked cropped, compare its aspect ratio against the platform target in the fit panel. If a web page is slow, look at the file size and dimensions and switch to WebP or AVIF. If the DPI shows 96 and is labelled estimated, the file simply has no print-DPI tag, which is normal for screenshots and web images and does not affect on-screen quality at all. And if an image will not open, it is likely a format your browser cannot decode, such as HEIC or TIFF — convert it first with the Image Converter tool and try again.
Armed with these definitions and the live numbers from the checker above, you can confidently answer any question about an image's size, print potential, web suitability or social fit — and you will never again have to guess whether a picture is good enough for the job.
Check any image's exact pixel dimensions, megapixels, aspect ratio, real or estimated DPI/PPI, print size at 72–600 DPI, dominant colors, EXIF metadata, an estimated quality score and how it fits print and social-media requirements — instantly and entirely in your browser, with nothing uploaded.
किसी भी इमेज के सटीक pixel dimensions, megapixels, aspect ratio, असली या अनुमानित DPI/PPI, 72–600 DPI पर print size, dominant colors, EXIF metadata, अनुमानित quality score और print/social-media fit तुरंत देखें — पूरी तरह आपके browser में, कुछ भी upload किए बिना।