What is the maximum data capacity of a QR code?

QR codes can store up to 7,089 numeric characters, 4,296 alphanumeric characters, 2,953 bytes of binary data, or 1,817 Japanese Kanji characters. The actual capacity depends on the version (size from 21×21 to 177×177 modules) and error correction level chosen. Higher error correction reduces capacity but improves scannability when damaged.

Can I decode a QR code from an image?

Yes! Switch to the "Decode" tab and upload a QR code image file (PNG, JPEG, GIF, BMP) or provide its URL. Click "Load" then "Decode" to extract the encoded data. The tool uses advanced image processing to handle rotated, skewed, or partially damaged QR codes. Results appear in the text area below for easy copying.

What error correction levels are available?

Four levels are available: L (Low - 7% recovery), M (Medium - 15%), Q (Quartile - 25%), and H (High - 30%). Higher levels allow the QR code to remain scannable even when damaged, dirty, or partially covered by a logo. Level H is recommended when adding logos or printing on textured surfaces. Lower levels produce simpler codes that scan faster.

Can I customize the QR code appearance?

Yes! You can change the foreground color (default black) and background color (default white) using the color pickers. You can also add a custom logo image to the center - use Level H error correction for best results with logos. Keep logos small (under 30% of QR size) and ensure good contrast. Custom colors should maintain high contrast for reliable scanning.

What types of data can I encode in a QR code?

QR codes support multiple data types: URLs/websites, plain text, email addresses (mailto:), phone numbers (tel:), SMS messages (sms:), WiFi credentials (WIFI:T:WPA;S:network;P:password;;), vCard contacts, geographic locations (geo:latitude,longitude), calendar events, and cryptocurrency addresses. Most smartphones automatically detect the type and offer appropriate actions (open browser, save contact, connect to WiFi).

Why won't my QR code scan properly?

Common issues: insufficient contrast between foreground/background colors, logo too large covering critical areas, error correction level too low for the amount of damage, image resolution too low when printed, or excessive compression artifacts. Solutions: use Level H error correction, keep logos under 30% size, maintain high contrast (dark on light), test print at actual size, and avoid gradient backgrounds.

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QRコード生成器

ビジネスカードやURL対応の無料QRコード作成ツール。簡単操作で即時生成・ダウンロード可能！今すぐお試しください。

ToolFK QRコード生成とは

URL・Wi-Fi 等を QR に。無料。バーコード生成、URL短縮。

主な機能

URL/テキスト/Wi-Fi
サイズ・訂正
PNG/SVG
プレビュー
高コントラスト
無料

How to Create a QR Code with ToolFK

ページを開く。
種別選択。
入力。
設定。
読取確認。
保存。

Frequently Asked Questions

期限?

URL 次第。

訂正?

M/Q/H。

ロゴ?

小さめ可。

形式?

SVG/PNG。

保存?

機密禁止。

読取?

コントラスト確認。

最終更新：2026年7月1日

QRコード生成器

ToolFK QRコード生成とは

主な機能

How to Create a QR Code with ToolFK

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関連ツール

Frequently Asked Questions

期限?

訂正?

ロゴ?

形式?

保存?

読取?