Color and dead pixels
Black, white, and RGB solids are the fastest way to catch dead pixels, bright pixels, dark pixels, and obvious tint imbalance.
Click to start fullscreen inspection
Inspect dead pixels, bright pixels, and dark pixels
Current: 純黒
#050505 · Press F for fullscreen
Device info
画面幅
--デバイスピクセル比
0.0色深度
--Refresh rate
--Controls
← →
Switch test colors F
Enter fullscreen Esc
Exit fullscreen入力欄以外ではショートカットが使えます。左右キーでパターン切替、F で全画面、Esc で終了です。
Color picker
純黒
#050505カスタム色
全画面の簡易チェックドット欠けと色偏り確認端末情報も同時表示
画面総合テスト
よく使う画面チェックを 1 ページにまとめ、単色切替、ドット欠け確認、全画面観察、ブラウザから見える端末情報表示を行えます。
Grayscale and tonal range
Step ladders, gradients, and clipping views make it easier to catch banding, crushed shadows, and blown highlights.
Sharpness and refresh behavior
Resolution and refresh views help inspect scaling, thin-line rendering, browser-side smoothness, and timing consistency.
Core test entries
If the overview already reveals a likely issue, jump into a more focused page for a deeper pass.
色表示テスト
全画面の単色とカスタム HEX 色を使って、色かぶり、ドット欠け、輝点、周辺のムラを確認します。
グレースケールテスト
階段状の灰色、滑らかなグラデーション、黒つぶれ、白飛び、バンディングで階調表現を確認します。
焼き付きテスト
静的な単色表示と手動開始の循環モードを使って、残像、残留画像、明確な焼き付き跡を確認します。
解像度テスト
現在の解像度、DPR、1px 線、ピクセルグリッド、鮮明度サンプルを確認し、ブラウザ上でどれだけシャープに見えるかを確かめます。
リフレッシュレートテスト
requestAnimationFrame によってブラウザ側のリフレッシュレートを推定し、簡易モーション表示と合わせて滑らかさや揺らぎを確認します。
Suggested test flow
This order mirrors how many people actually check a new monitor or troubleshoot a panel at their desk.
Start with solid colors
Use black, white, and RGB first to reveal dead pixels, bright pixels, glow, corner shading, and obvious tint shifts.
Move to grayscale next
If the panel looks washed out, crushed, or uneven in tone, switch to ladders and gradients for a more sensitive read.
Check sharpness after that
Use 1px lines, checker patterns, and text sharpness views to inspect scaling artifacts and rendering softness.
Use focused pages last
Once you know which direction to investigate, the dedicated color, grayscale, burn-in, resolution, or refresh pages will be more efficient.
Screen self-check guide
The reading path stays below the workbench so the first screen stays usable without hiding the deeper context.
Why solid colors come first
Solid-color patterns are the usual starting point for a quick display check because they are fast to read with the naked eye.
What grayscale and sharpness reveal
When solid colors look mostly fine, grayscale and fine-line views help dig deeper into tonal separation and rendering quality.
How to read each pattern
Each pattern is better at revealing a different class of display issue, so switching with intent saves time.
クイックチェック
純黒
暗点、バックライトのにじみ、基本的なパネル均一性の確認に使います。
クイックチェック
純白
輝点、汚れ、明るさの均一性を素早く確認するのに適しています。
クイックチェック
赤チャンネル
赤画面はスティックピクセルや明確な色かぶりを見つけやすくします。
クイックチェック
緑チャンネル
緑画面はドット欠けやスティックピクセルを見分けやすくします。
クイックチェック
青チャンネル
青画面は暗い隅、スティックピクセル、均一性の変化を確認するのに役立ちます。
クイックチェック
グレー階段
黒から白までの階調分離が自然かを素早く確認します。
クイックチェック
チェッカーパターン
拡大縮小のアーティファクトや輪郭の鮮明さを確認するためのパターンです。
Screen self-check guide
The reading path stays below the workbench so the first screen stays usable without hiding the deeper context.
Why solid colors come first
Solid-color patterns are the usual starting point for a quick display check because they are fast to read with the naked eye.
Black surfaces expose dark issues
Pure black helps reveal dark pixels, backlight glow, gray corners, and dark-scene uniformity shifts.
White surfaces expose bright issues
Pure white makes bright pixels, dust, stains, and bright-area uniformity issues easier to notice.
What grayscale and sharpness reveal
When solid colors look mostly fine, grayscale and fine-line views help dig deeper into tonal separation and rendering quality.
Grayscale reveals tonal collapse
If neighboring tones merge too early or gradients band visibly, the display path is not separating tones smoothly enough.
1px lines reveal scaling behavior
Blurry or broken fine lines often point to system scaling, browser zoom, or rendering-path interpolation.
Where web testing stops
SPCBOX focuses on browser-reachable self-checks rather than pretending to expose low-level monitor truth.
The readings are browser-side
Resolution, DPR, color depth, and refresh estimates come from the current browser environment and should be read as practical hints.
Pro calibration still needs hardware
For absolute color accuracy, gamma curves, luminance calibration, or hardware response validation, dedicated physical instruments are still the right tool.
Common questions
These answers clarify what a browser-based screen test can help with and where its limits begin.
Q.
Can this replace professional display instruments?
No. It is best for fast dead-pixel, tint, grayscale, sharpness, and browser-side motion checks, not for replacing a calibrator or high-speed camera setup.
Q.
Why does fullscreen matter so much?
Fullscreen reduces browser chrome, nearby distractions, and layout edges, which makes glow, dead pixels, corner shading, and uniformity issues easier to spot.
Q.
Why is the refresh result not identical to my monitor spec?
Because this page estimates behavior through requestAnimationFrame, so the result is influenced by focus state, browser scheduling, and system load.
Q.
Do I need the dedicated subpages if the overview looks fine?
Not always. The overview is intentionally built for fast screening, and the focused pages are most useful once you already have a suspected direction.