Image Resolution Converter

無料画像解像度換算ツール — DPI、PPI、CMあたりのドット数などを瞬時に換算

OmniConverterの無料オンライン画像解像度換算ツールで、DPI、PPI、ドット/センチメートル、ドット/ミリメートルの間を即座に換算。日本の印刷業界の350 DPI標準、医用画像DICOMの解像度仕様、Webサイトの画像最適化まで対応。グラフィックデザイナー、写真家、印刷会社のプロフェッショナルに欠かせないツールです。

使い方

簡単な3ステップで変換できます。

1

画像解像度の値を入力

2

変換元と変換先の解像度単位を選択

3

変換後の解像度を確認

人気の換算

一般的な基準

参照

1 DPIDPI

1 DPI

参照

1 DPIPPI

1 PPI

参照

1 DPIdot/m

39.3700787402 dot/m

参照

1 DPIdot/cm

0.3937007874 dot/cm

参照

1 DPIdot/mm

0.0393700787 dot/mm

参照

1 DPIpx/cm

0.3937007874 px/cm

参照

1 DPIpx/mm

0.0393700787 px/mm

実用的なユースケース

日本の印刷業界では、オフセット印刷の標準解像度は350 DPI(日本では300 DPIではなく350 DPIが一般的)。A4サイズのチラシには3,504×2,480ピクセル(350 DPI)が必要です。プロのカメラマン(Canon、Nikon、Sony αを使用)が雑誌や広告に納品する画像は350 PPI、CMYKで入稿します。Web用の画像は72 PPIが基準ですが、iPhoneのRetinaディスプレイ(326 PPI)やMacBook Pro(254 PPI)の高精細画面では、画像を2倍〜3倍のサイズで書き出します。スキャナーは文書300 DPI、写真600 DPI、フィルムは2,400〜4,800 DPIでスキャンします。医療画像のDICOMではCTが512×512、MRIが1,024×1,024が基本。印刷会社(大日本印刷、共同印刷など)への入稿は、350 DPI以上が推奨されています。WebデザインではFigmaで1倍のデザインカンプを作り、@2x、@3xのアイコンを一括書き出しします。地図では国土地理院の地形図をGeoTIFF形式で提供。4K/8Kテレビの解像度も3840×2160 / 7680×4320ピクセルとPPI(50-80 PPI程度)が関係します。プロジェクターの解像度もXGA(1024×768)から4K(4096×2160)まで様々で、画面サイズとの関係でPPIが変わります。写真のdpi/ppiを間違えるとプリント時に粗さが出ます。

よくある質問

よくある換算の質問への回答

350DPI印刷とは?+

350 DPI = 1インチあたり350ドット。日本の高品質印刷では350 DPIが標準です。名刺は350 DPI推奨。

DICOMとは?+

DICOMは医療用画像の国際標準。日本の病院では放射線画像やCTで72-300 DPIが使われます。

DPIとPPIの違いは?+

DPIは印刷、PPIは画面表示の解像度です。数値は同じでも用途が異なります。

DPIを点/cmに換算するには?+

DPIを2.54で割ります。

Web画像の解像度は?+

Web標準72 PPI。Retinaディスプレイは144 PPI以上。

px/cmをDPIに換算するには?+

px/cmに2.54を掛けます。

印刷に必要な解像度は?+

雑誌印刷350 DPI、新聞200 DPI、ポスター150 DPI。品質により異なります。

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