Placeholder Image Generator (Colored Blocks, Any Size)

Generate solid-color or gradient placeholder images at any size - download PNG

🔒 100% ブラウザ内🆓 ずっと無料⚡ サインアップ不要
注意: 下記のツールインターフェースは現時点で英語のみに対応しています。UI の翻訳は順次進めています。 このツールを英語で見る →
Presets

使い方

  1. 1
    Enter width × height

    Any dimension, or pick a preset - square avatar, 16:9 hero, 4:3 card, story 9:16, banner sizes.

  2. 2
    Pick a fill

    Solid color, gradient, or checkerboard. Toggle the dimensions label overlay.

  3. 3
    Download the PNG

    Or copy a data URI to paste directly into HTML/CSS/JSX.

Placeholder Image Generator (Colored Blocks, Any Size) について

Free placeholder image generator. Type any width and height (or pick a preset) to get a solid-color or gradient placeholder with the dimensions printed on it - perfect for mockups, AI-generated app screens, and design comps. Download as PNG. Runs entirely in your browser. 712 Tools の Placeholder Image Generator (Colored Blocks, Any Size) はモダンな JavaScript API を使って完全にブラウザ内で動作します - サーバーがあなたのデータを見ることは一切ありません。つまり、即時の結果、完全なプライバシー、アップロード制限なしです。

デバッグ、簡単な確認、あるいは本番のインシデント対応まで - このツールは何度でも無料で使えます。ウォーターマークなし、サインアップなし、ツール内広告なし。

よくある質問

Why not just use via.placeholder.com?

That's fine when it's up - but external placeholder services regularly go down and expose your mockups to their tracking. This tool generates the PNG in your browser, no request made.

Can I embed placeholders inline?

Yes - the tool also outputs a data URI you can paste directly into <img src="data:image/png;base64,…">. No network request needed.

Is there a size limit?

Bound by your browser - canvases up to ~8000×8000 work on most laptops. Way beyond typical mockup needs.

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