WCAG Contrast Checker

示例文字 Aa

这是普通文本示例 (Normal Text)

这是小号文本示例 (Small Text)

21.00:1
对比度
WCAG AA
普通文本 ≥ 4.5:1
✓
WCAG AA (大文本)
大文本 ≥ 3:1
✓
WCAG AAA
普通文本 ≥ 7:1
✓
WCAG AAA (大文本)
大文本 ≥ 4.5:1
✓

WCAG 标准说明

  • WCAG AA：最低可接受标准，普通文本对比度 ≥ 4.5:1，大文本（≥ 18pt 或 14pt 粗体）≥ 3:1
  • WCAG AAA：更高可访问性标准，普通文本对比度 ≥ 7:1，大文本 ≥ 4.5:1
  • 对比度计算：基于 WCAG 2.1 标准，使用相对亮度公式计算
  • 应用场景：网页设计、UI 设计、文档设计等需要确保可访问性的场景
  • 建议：至少满足 WCAG AA 标准，关键内容建议达到 AAA 标准

What is Wcag Contrast Checker?

Convert, resize, compress, or tweak your images — all without leaving your browser. Your photos never touch a server, so there is zero risk of leaks or uploads. Whether you are prepping images for a website, shrinking a file for an email, or just converting formats, this tool gets it done quickly.

▶Use Cases5 scenarios
  • ◆Sizing photos for Instagram and Twitter
  • ◆Compressing images to speed up your website
  • ◆Cropping and resizing passport photos
  • ◆Prepping product shots for your online store
  • ◆Converting between image formats
▶How to Use6 steps
  1. 1Open the Wcag Contrast Checker — no signup, no login.
  2. 2Paste your input or drag and drop a file.
  3. 3Hit Process or Generate and see results instantly.
  4. 4Preview the output and click Copy to grab it.
  5. 5💡 Pro Tip: Check the FAQ below for power-user tricks.
  6. 6📌 Bookmark this page — you will want to come back.
▶Features8 features
  • ✓Completely free
  • ✓No account needed
  • ✓Runs in your browser
  • ✓Supports all major formats
  • ✓Live preview
  • ✓Download with one click
  • ✓Your images stay private
  • ✓Works on any device
▶FAQ7 questions
What is Wcag Contrast Checker?

An online image processing tool. Input: the raw data or content you need to process. Output: the processed result with one-click copy and download. Used for quick processing tasks in development, work, and study. Everything runs locally in your browser — no data is uploaded.

What formats can I use?

JPG, PNG, WebP, GIF, BMP — all the usual suspects. If your camera or phone can save it, we probably handle it.

Are my images uploaded anywhere?

Never. Everything happens inside your browser. Your photos stay on your device.

Is there a file size limit?

For the smoothest experience, keep images under 10 MB. Larger files usually work too, just might take a moment longer.

Can I process multiple images at once?

One at a time for now, but batch mode is on our roadmap.

Will my images lose quality?

For conversions, you control the quality slider. We default to a sweet spot between size and clarity.

Does it work on phones?

Yes — and you can pick images straight from your camera roll.