Practical guide
How to Create a QR Code That Scans Reliably
A QR code stores text or a link in a pattern a phone camera can read. The SmartEdgeTools QR Code Generator creates the code entirely in your browser as a 300-pixel PNG image you can download. This guide explains what to put in a code, how to test it, and how to print or share it so it still scans.
By Ather Saud · Updated on November 1, 2026
What to put in the code
Enter the exact text or URL you want the scanner to receive, then select Generate QR Code. For a website, use the full address, including https://, and check for typos before generating, because a small typo sends people to the wrong page or to no page at all. For plain text, keep it short: the tool reports an error for input it cannot encode and suggests shorter text.
Do not put passwords, private keys, or sensitive personal data in a QR code. Anyone who can see the printed code can scan it and read the contents. For a link that may change, use a stable page you control rather than a temporary address, or be ready to reprint the code when the address changes.
Test before you print or share
Scan the generated code with a phone camera and with a second phone if possible, and confirm it opens the intended page or shows the intended text. Test at the size and distance people will actually use: a code that scans on a large screen may fail when printed small, and a code on a curved or glossy surface may fail from glare.
Keep good contrast and a clear margin around the code. The tool uses a margin of 1 module around the pattern. Do not cover the centre with a large logo, do not stretch the image so the squares become rectangles, and do not place text or graphics over the pattern.
Size, download, and printing
Select Download QR Code to save the image as qrcode.png, a 300-pixel square image. That size is suitable for screens and for small print, such as a card or a label. For a large poster, a 300-pixel image may look soft when enlarged, so test a printed copy at the final size before producing many copies.
If the printed code fails, print it larger, increase contrast, use matte paper if glare is a problem, and test again. If the content is long, shorten the URL or the text where possible, because shorter content generally produces a simpler, easier-to-scan pattern.
What a QR code does not do
A QR code does not check that a link is safe, does not hide its contents, and does not track scans by itself. A scanner will show the link or text before opening it in most cases, so check the destination before following an unfamiliar code. The generator does not create a tracking link, a login page, or a payment page; it only encodes the text you enter.
| Check | Good practice | Avoid |
|---|---|---|
| Content | Full, checked URL or short text | Typos, passwords, or private data |
| Test | Scan on a phone at real size and distance | Sharing without a test scan |
| High contrast, clear margin, tested final size | Stretching, covering, or tiny printing |
Key takeaways
- Use the full, checked URL and keep text short.
- Test the code at the size and distance people will use.
- The download is a 300-pixel PNG, so test large prints before mass printing.
Frequently asked questions
What file do I get when I download a QR code?
A PNG image named qrcode.png, 300 pixels square, generated in your browser.
Why does my QR code not scan?
Common causes are low contrast, a code printed too small, glare, a covered pattern, or a stretched image. Print larger, restore contrast and margin, and test again.
Can I put a password in a QR code?
You should not. Anyone who sees the code can scan it, so treat QR contents as visible to anyone with the image.
Is my QR text uploaded?
The code is generated in the browser, and the tool's code does not send the text you enter to a server to create the image.