How do I generate a QR code for a URL?

Paste your URL into the input field and click Generate. The QR code is created instantly in your browser. You can then download it as a PNG image for use in print materials, presentations, or websites.

Is there a size limit for QR code content?

This tool supports up to about 2,953 bytes in Byte mode for plain text (UTF-8), or about 984 Japanese (UTF-8) characters, at the default error correction level. For best scannability, keep your content short. URLs are the most common use case and work well. Shorter content produces simpler QR codes that are easier to scan.

Are the generated QR codes free to use commercially?

Yes, QR codes generated by this tool are completely free to use for any purpose, including commercial use. The QR code standard is open and no license is required. All generation happens in your browser with no server dependency.

QR Code Generator

ブラウザ内で処理

テキストやURL、Wi-Fi接続情報からQRコードを生成・ダウンロードします。全てブラウザ内で処理。

How to Use the QR Code Generator

This free online QR code generator creates QR codes from any text or URL entirely in your browser. Simply type or paste your content into the input field and click "Generate" to create a QR code instantly. You can then download the QR code as a PNG image for use in print materials, presentations, websites, or social media. No data is sent to any server, and no external APIs are used, making this tool completely private and fast.

What is a QR Code?

A QR code (Quick Response code) is a two-dimensional barcode that can store text, URLs, contact information, and other data. QR codes were invented in 1994 by Denso Wave for tracking automotive parts and have since become ubiquitous in marketing, payments, event ticketing, restaurant menus, and more. Any smartphone camera can scan a QR code to instantly access the encoded information, making them an incredibly convenient bridge between the physical and digital worlds.

Common Use Cases

QR codes are used for sharing website URLs without typing, adding Wi-Fi network credentials for easy connection, encoding contact information (vCards), linking to app downloads, directing customers to product information or reviews, enabling mobile payments, and providing quick access to event tickets or boarding passes. Businesses use QR codes on business cards, flyers, product packaging, and storefronts to drive digital engagement.

Tips for Effective QR Codes

Keep the encoded content short for better scannability. URLs are the most common use case and work well. Always test your QR code with multiple devices before distributing it. When printing, ensure sufficient contrast between the dark modules and light background, and leave a quiet zone (white border) around the code. Larger QR codes are easier to scan from a distance, so size the code appropriately for its intended viewing distance.

QRコード生成ツールの使い方

テキストやURLを入力し「生成」ボタンを押すだけで、ブラウザ内でQRコードを即座に作成できます。生成されたQRコードはPNG画像としてダウンロード可能です。外部サーバーへのデータ送信は一切なく、完全にプライベートかつ高速に動作します。印刷物やプレゼン、SNSなど幅広い用途にご活用ください。

QRコードが読み取れない原因 / Why QR Codes Fail to Scan

落とし穴 / Pitfall	問題 / Problem	対処 / Fix
印刷したら読み取れない Printed code won't scan	サイズ不足・余白(クワイエットゾーン)不足・低解像度印刷 Too small, no quiet zone, or low DPI	印刷は2cm角以上+周囲に4セル分の余白を確保 Print at 2cm+ with a 4-module quiet zone
情報を詰め込みすぎて密になる Overly dense codes	長いURLや全文テキストでセルが細かくなり読み取り率が低下 Long data shrinks modules	URLは短くする(ただし短縮サービスは寿命と信頼性に注意) Shorten the URL itself when possible
色付き・反転で読めない Colored or inverted codes fail	背景より暗いコードが前提。コントラスト不足や白黒反転はNG Scanners expect dark-on-light with strong contrast	暗色コード+明色背景を維持。コントラスト確認を Keep dark modules on a light background
遠距離掲示で読めない Unscannable from a distance	読み取り距離はコードサイズの約10倍が目安 Scan distance ≈ 10x code size	ポスター掲示なら一辺10cm以上に拡大 Scale up for posters
後からリンク先を変えたい Need to change the destination later	QRに埋めたURLは印刷後変更不可 The encoded URL is immutable once printed	自サイト経由のリダイレクトURLを埋めておく Encode a redirect URL you control

用途別の目安 / Size Guide

名刺:        1.5〜2cm角(短いURL推奨)
チラシ:      2〜3cm角
ポスター:    10cm角以上(掲示距離次第)
画面表示:    200px角以上

図1: QRコードの構造(ファインダーパターンとクワイエットゾーン)

未公開URL・Wi-Fi情報を端末内でQR化 / Encode private URLs and Wi-Fi details as QR codes locally

Many QR generators are server-side — meaning the URL you encode (an unreleased campaign page, a private document link, Wi-Fi credentials) is logged before you ever print it. This tool renders the QR code entirely in your browser: the content never leaves your device, and generation works offline. Zero requests in the DevTools Network tab.

QR化する内容は未公開キャンペーンURLやWi-Fi情報など事前に漏らしたくないものが多いはず。本ツールは生成がブラウザ内で完結し、内容が外部に記録されることはありません。

Wi-Fi接続用QRコードの作り方 / Wi-Fi QR codes

「Wi-Fi」タブでSSID・暗号化方式・パスワードを入力して生成すると、iPhone(iOS 11以降)やAndroid(10以降)の標準カメラで読み取るだけで接続できるQRコードになります。来客用Wi-Fiの掲示や、店舗・オフィスのゲスト回線の案内に便利です。中身は次のような決まった書式の文字列で、SSIDやパスワードに含まれる ; , : " \ は自動でエスケープします。

WIFI:T:WPA;S:MyHome-5G;P:パスワード;;
WIFI:T:nopass;S:Guest;;            (暗号化なし)
WIFI:T:WPA;S:Hidden;P:xxxx;H:true;; (ステルスSSID)

The Wi-Fi tab builds the standard WIFI:T:...;S:...;P:...;; payload. WPA covers WPA2/WPA3. Special characters are escaped automatically, and the password is never stored or sent.

🔒 すべての処理はブラウザ内で完結し、入力データはサーバーへ送信されません。登録不要・無料。 / All processing runs in your browser; nothing is uploaded. Free, no sign-up. プライバシーポリシー / Privacy Policy

参考資料 / References

ISO/IEC 18004: QR Code bar code symbology