Image DPI Changer
Convert image to 300 DPI (or any value) online — free and lossless. Check the current DPI of any JPG or PNG, set a new one, and download. Works with AI-generated images from ChatGPT, Midjourney and other tools that default to 72 DPI. Your files never leave your browser.
More DPI tools & guides
The changer above rewrites density metadata losslessly. These extra pages cover checking a file first, converting specifically to 300 DPI, raising a rejected tag, and the DPI vs PPI distinction.
DPI Checker
Read JPEG JFIF/EXIF and PNG pHYs density, pixel size, and print size. Read-only — the file is never rewritten.
Convert to 300 DPI
The print-shop default. Same lossless rewrite, target pre-filled at 300 for journals, ID photos, and Etsy printables.
Increase Image DPI
Raise a 72 or 96 tag so preflight stops rejecting the file. Increasing DPI does not add pixels.
DPI vs PPI
When the two terms are interchangeable, and the few cases — print and scan — where the difference matters.
How to convert an image to 300 DPI online
Add your images
Drop JPG or PNG files above. The current DPI of each image is detected and shown instantly — this doubles as a free DPI checker.
Choose the target DPI
Pick 300 DPI — the print standard — or 72, 150, 200, 600, or any custom value your print shop, journal, or marketplace requires.
Download
Click Download. The DPI metadata is rewritten losslessly on your device: pixels are untouched, quality is identical, and nothing is uploaded.
What is DPI — and why it doesn't change your pixels
DPI (dots per inch) is a single metadata value that tells printers how densely to place your image's pixels on paper. A 3000×2000 px photo contains exactly the same pixels at 72 DPI and at 300 DPI — the only difference is the intended print size: 41.7×27.8 inches versus 10×6.7 inches.
That's why this image DPI converter never re-encodes your picture. It rewrites the resolution fields (JFIF & EXIF for JPG, the pHYs chunk for PNG) and leaves every pixel byte exactly as it was. Tools that "convert DPI" by re-saving the image quietly degrade quality — there is no reason to.
Print size at 300 DPI — quick reference
To print sharp at 300 DPI, your image needs roughly these pixel dimensions:
| Print size | Pixels needed @ 300 DPI | Common use |
|---|---|---|
| 4 × 6 in (10×15 cm) | 1200 × 1800 px | Standard photo print |
| 5 × 7 in (13×18 cm) | 1500 × 2100 px | Portrait print |
| 8 × 10 in (20×25 cm) | 2400 × 3000 px | Framed photo |
| 8.5 × 11 in (US Letter) | 2550 × 3300 px | Documents, KDP interiors |
| A4 (21 × 29.7 cm) | 2480 × 3508 px | Posters, printables |
| 12 × 18 in | 3600 × 5400 px | Large prints |
Drop an image into the tool above and it shows the exact print size at your chosen DPI automatically.
Image DPI calculator — pixels ⇄ print size
Use this quick image DPI calculator to see how large your photo will print, or how many pixels you need for a target print size.
Who needs a 300 DPI image?
Print shops and photo labs, academic journals and conference papers, Amazon KDP book covers and interiors, Etsy printables, embroidery and engraving services, passport and ID photo requirements, magazine ads — all of them routinely reject files whose DPI metadata isn't set to 300. Fixing it takes seconds here and costs nothing.
AI image creators are the newest addition to that list. Images generated by ChatGPT, Midjourney, DALL-E, Stable Diffusion and Google Gemini are typically saved at 72 DPI — fine for screens, but rejected by every print workflow that checks the tag. The pixels are usually large enough (1024×1024 or bigger); only the density label is wrong. Drop the AI-generated image here, set 300 DPI, and the file is print-ready without any upscaling or quality loss.
Common image DPI requirements at a glance
Different platforms and print services ask for different resolution settings. These are the values you will most often be asked for:
| Use case | Required DPI | Notes |
|---|---|---|
| Amazon KDP covers & interiors | 300 DPI | Files below 300 DPI trigger print-quality warnings |
| Academic journals & papers | 300–600 DPI | Line art and charts often need 600 DPI |
| Etsy printables & wall art | 300 DPI | Buyers expect crisp prints up to A4 and beyond |
| US passport photo (2 × 2 in) | 300 DPI | 600 × 600 px at 300 DPI meets the official spec |
| Magazine & newspaper ads | 300 DPI | CMYK delivery is usually requested as well |
| Large-format posters & banners | 150 DPI | Viewed from a distance, so lower density is fine |
| Web & social media | 72–96 DPI | Screens ignore DPI — only pixel dimensions matter |
When a submission form rejects your file for "low resolution", it is almost always this single metadata number — change the image DPI to the required value above and re-upload the very same picture.
Why print services reject files over one number
The rejection email rarely explains itself, so here is what actually happens on the other side, in the three places people hit it most:
At the print shop. Commercial printers run every order through preflight software before a human ever sees it. That software reads one field — the DPI metadata — to decide how large your file will print. A 3000 × 2400 px photo tagged 72 DPI claims it wants to print 41 inches wide; the system compares that against your ordered 10 × 8 in print, concludes the file is "low resolution", and bounces it. The pixels were enough all along — a 300 DPI tag makes the same file claim exactly 10 × 8, and preflight waves it through.
At the journal or conference. Publishers put "figures at 300 DPI minimum, 600 for line art" in their author guidelines because page layout happens months later, by someone who never saw your screen. The metadata is the only instruction that survives the hand-off: it tells the typesetter how big the figure can safely sit on the page. Submissions systems increasingly enforce it automatically — the manuscript uploads, the figure check fails, and the revision clock starts over a field you can edit in two seconds.
At the marketplace. Stock libraries, print-on-demand platforms and Etsy digital-download buyers all treat the DPI tag as a promise about print quality. A printable tagged 96 DPI collects "blurry when printed" reviews not because the pixels were bad, but because buyers' home printers obeyed the tag and stretched the image. Sellers who set 300 DPI before uploading are making the same file keep its promise.
In all three cases nothing about your actual image was wrong — the label was. That is the whole reason this tool exists: correct the label, keep every pixel byte-identical, and re-submit.
Changing image DPI without Photoshop
You can change DPI in desktop software, but every route is slower than a browser tool — and some quietly resample your pixels along the way:
Photoshop — Image → Image Size, untick "Resample", type a new resolution. Safe, but it needs a subscription and a download. GIMP — Image → Print Size, set the X and Y resolution. Free, yet a 200 MB install is overkill for a metadata edit. macOS Preview — Tools → Adjust Size can resample your image if the wrong boxes are ticked, silently changing your pixels. Windows — offers no built-in way to change DPI at all.
SetDPI performs the same lossless metadata edit in one drag-and-drop, with no install, no account and no upload — which is exactly why an image DPI changer belongs in the browser.
Image DPI changer — frequently asked questions
How do I convert an image to 300 DPI online for free?
Does changing DPI reduce image quality?
Will changing DPI change the file size or resolution?
How do I check the DPI of an image?
What DPI do I need for printing?
What's the difference between 72 DPI and 300 DPI?
Can I change the DPI of a PNG?
pHYs chunk, and SetDPI writes it losslessly — just like the JFIF and EXIF resolution fields in JPG files.How do I change the DPI of an image without Photoshop?
Is DPI the same as PPI?
What DPI should I use for scanning photos and documents?
How do I change the DPI of an AI-generated image?
Are my photos uploaded to a server?
Privacy
The full privacy policy, including Google AdSense, is on the Privacy page.
Your images never leave your device. SetDPI rewrites the DPI metadata entirely in your browser — there is no upload, no server-side processing, and no copy of your file anywhere but your own computer. There are no accounts and no forms, so the site itself never asks you for anything about yourself — the analytics below are a separate matter.
The site does use two third-party analytics services to see aggregate traffic:
- Google Analytics 4 — page views and events. GA4 uses your IP address to derive a coarse location (country, region, city); Google states it does not log or store individual IP addresses for visitors from the EU, Switzerland and the UK. This site sends GA4 exactly one event of its own, and only when a file is rejected: it reports the file's extension and nothing else — not the name, not the size, not a single byte of the image. It exists to answer one question with real numbers rather than guesswork: which formats do people actually arrive with that this tool cannot yet read.
- Microsoft Clarity — session replays and heatmaps, used to spot usability problems. Clarity reconstructs a visit rather than just counting it: pointer movement, clicks, scrolling, and the content shown on the page while you used it. The file name shown beside each preview is marked so that Clarity records the space it occupies but not the text in it — people bring passport and ID scans here, and a file name on its own can carry a real one. The image data is never sent either; a replay shows the page, not your picture.
Both set cookies, and neither is tied to a name or account because we don't have those. You can block them with a browser ad-blocker or by disabling cookies, with no effect on the DPI tool working. Google AdSense may also set cookies to serve ads — you can opt out of personalised advertising via Google Ads Settings.
One more third party, for completeness: the footer on this page shows a badge image served from SaaSHub's CDN. Loading an image from another host lets that host see your IP address and browser string as it serves the file; this one sets no cookie, and it is on the homepage only.
Your data rights
Some of what those two analytics tools collect — an IP address, a browser and device string, a record of what was clicked and scrolled, a replay of the page as you saw it — counts as personal data under EU, UK and California law, even though nothing here ties it to a name. So the rights below apply. To be clear about what this section is: a description of those rights and of how to use them, not a claim that this one-person site has been certified compliant with anything; advertising is covered on the Privacy page.
Where the data actually sits matters for every request that follows. SetDPI runs no server and keeps no database — the pages are static files, there is no account, no sign-up and no form anywhere on the site. The only copies of the analytics data are the ones held inside Google Analytics and Microsoft Clarity, and how long each keeps it is set by that provider's own retention policy rather than by any setting here. Their terms are in Google's privacy policy and Microsoft's privacy statement.
EU and UK visitors (GDPR and UK GDPR)
You have the right to access the data held about you, to have it rectified if it is wrong, to have it erased, to restrict how it is processed, to object to the processing, and to receive your data in a portable form. You also have the right to lodge a complaint with your national supervisory authority, and you do not need to go through this site first to do it.
Practically, an access or erasure request sent to this site has nothing to act on, because there is no record of you here to look up or delete. The parties that do hold something are Google and Microsoft, and both run their own request channels — the policies linked above are the route in. The step that takes effect immediately, without asking anyone, is in the last section below.
California visitors (CCPA and CPRA)
- Right to know what is collected and who receives it. Analytics recipients listed above: page views and events to Google Analytics, and session replays and heatmaps to Microsoft Clarity. Google AdSense may also receive cookie identifiers to serve ads; that is described in the privacy policy. On this page only, SaaSHub's CDN additionally sees your IP address and browser string when it serves the badge image. This site itself stores nothing.
- Right to delete and right to correct. As above, the copies live with Google and Microsoft, so those requests have to go to them to reach anything.
- Right to opt out of the sale or sharing of personal information. See the note directly below.
- Right to non-discrimination for exercising any of these. Every tool and page here is free, with no account and no paid tier, so there is nothing that could be withheld from you. Blocking the analytics does not change what you can use.
On “sale” and “sharing”: nothing is sold for money. Google AdSense is loaded on these pages and may use cookies to serve ads, including ads based on other sites you have visited; how to opt out is in the privacy policy. The CCPA also counts disclosing identifiers for cross-context behavioural advertising as “sharing”, and personalized ads from Google AdSense can fall under that. Separately, Google Analytics and Microsoft Clarity each receive an identifier when your browser loads their script, and what they may then do with it is governed by their own terms rather than by anything configured here. If you would rather they did not receive it at all, block it — that is a real opt-out, and it takes effect the moment you set it.
How to stop the collection yourself
All of it depends on third-party scripts and cookies, so blocking is effective and needs no request to anyone:
- Any content or ad blocker — uBlock Origin, AdGuard, Brave's shields, Safari's tracking prevention — stops both scripts from loading at all.
- Blocking third-party cookies in your browser settings stops the cookies they set.
- Google's Analytics opt-out browser add-on disables Google Analytics on every site you visit, not just this one.
- Turning on Global Privacy Control in a browser that supports it sends an opt-out signal automatically; California law treats that signal as a valid opt-out request.
None of this affects the tool. The DPI changer is plain JavaScript inside the page and never calls the analytics scripts, so with both blocked you can still drop a file in, set the DPI and download it — offline, too, once the page has loaded. And whichever way you set it, the image itself still goes nowhere: nothing in this site's code uploads your file.