免费网站速度测试

测量网站加载速度，找出性能瓶颈。获取Core Web Vitals评分和改进建议。

什么是网站速度测试？

网站速度测试测量页面加载时间、性能评分、Core Web Vitals等。页面速度对用户体验和SEO都有重大影响。

Google将页面速度作为排名因素。慢的网站搜索排名下降，访客跳出率增加。本工具帮助找出并改善问题。

Key Performance Optimization Areas

Image Optimization

Images account for 50-80% of page weight on most sites. Converting to WebP/AVIF, lazy loading, and responsive sizing can cut load times in half.

Code Efficiency

Minification, tree-shaking, and code splitting ensure users only download the JavaScript and CSS they need for the current page.

Server & Hosting

Server response time (TTFB) sets the baseline for all other metrics. Edge hosting and CDNs serve content from locations nearest your users.

Render Performance

Critical CSS inlining, font optimization, and avoiding render-blocking resources ensure content appears on screen as fast as possible.

Caching Strategy

Browser caching, service workers, and CDN caching eliminate re-downloads for returning visitors, making repeat visits near-instant.

Third-Party Scripts

Analytics, chat widgets, ad pixels, and social embeds can add 500KB+ to your page. Deferring or lazy-loading these scripts is critical.

Understanding Core Web Vitals

Google measures these metrics to evaluate real-world user experience on your site.

LCP

Largest Contentful Paint

Measures how quickly the main content of a page loads. This is usually the hero image, heading, or largest text block visible in the viewport. A fast LCP tells users the page is useful.

Good: under 2.5 seconds

INP

Interaction to Next Paint

Measures how quickly your page responds to user interactions like clicks, taps, and key presses. INP replaced FID in March 2024 as the primary responsiveness metric. It captures the full interaction lifecycle.

Good: under 200 milliseconds

CLS

Cumulative Layout Shift

Measures visual stability — how much content shifts around unexpectedly while the page loads. Images without dimensions, dynamically injected content, and web fonts are common causes of layout shift.

Good: under 0.1

FID

First Input Delay

Measures the time from when a user first interacts with your page to when the browser begins processing that interaction. Heavy JavaScript execution on the main thread is the primary cause of high FID.

Good: under 100 milliseconds

速度改进建议

1

Optimize all images

Convert images to WebP or AVIF format (30-50% smaller than JPEG/PNG). Use responsive srcset attributes so mobile users don't download desktop-sized images. Lazy-load images below the fold.

2

Minify CSS, JS, and HTML

Remove whitespace, comments, and unused code from all assets. Use tree-shaking to eliminate dead code from JavaScript bundles. This typically reduces file sizes by 20-40%.

3

Use a CDN

Content Delivery Networks serve your files from servers closest to each visitor. Cloudflare (free), AWS CloudFront, or Fastly can reduce latency by 50-80% for international visitors.

4

Reduce HTTP requests

Each file request adds latency. Combine CSS files, inline critical styles, use CSS sprites for icons, and lazy-load non-essential resources. Aim for under 50 requests per page.

5

Enable Brotli/GZIP compression

Server-side compression reduces text-based file sizes by 60-80%. Brotli offers 15-25% better compression than GZIP. Most modern servers and CDNs support both.

6

Monitor performance regularly

Performance degrades over time as features are added. Set up automated monitoring with Lighthouse CI, SpeedCurve, or WebPageTest to catch regressions before they impact users.

速度测试：Kleap vs 替代方案

功能KleapPageSpeed InsightsGTmetrixPingdom
Analysis typeConfig-based adviceLive URL testLive URL testLive URL test
价格完全免费免费免费/付费Free (limited)
Needs live URLNo (works pre-launch)YesYesYes
Personalized tipsFramework-specificGenericGenericBasic
Framework guidanceWordPress, React, Wix, etc.NoNoNo
Core Web VitalsEstimatedReal dataReal dataPartial

People Also Ask

What is a good website speed score?+
A good PageSpeed Insights score is 90 or above (out of 100). Scores between 50-89 indicate room for improvement, and below 50 is considered poor. However, what matters most is passing Core Web Vitals thresholds: LCP under 2.5 seconds, INP under 200 milliseconds, and CLS under 0.1. These are the metrics Google actually uses for ranking.
How does page speed affect SEO rankings?+
Google confirmed that page speed is a ranking factor, especially for mobile searches. Since 2021, Core Web Vitals are part of Google's Page Experience signals. While content quality still outweighs speed, when two pages have similar content quality, the faster page will rank higher. Slow pages also have higher bounce rates, which indirectly hurts rankings.
What causes a slow website?+
The most common causes of slow websites are: unoptimized images (50-80% of page weight), too many third-party scripts (analytics, ads, chat widgets), render-blocking CSS and JavaScript, no CDN or slow hosting, unminified code, too many HTTP requests, and missing browser caching headers. Most sites can improve by 50% just by optimizing images and deferring scripts.
How can I make my WordPress site faster?+
Install a caching plugin (WP Rocket, W3 Total Cache), optimize images with ShortPixel or Imagify, use a CDN like Cloudflare (free), minimize plugins (each adds JavaScript), choose a lightweight theme (GeneratePress, Astra), enable GZIP compression, and implement lazy loading for images and videos. These changes typically improve load times by 40-70%.
What are Core Web Vitals and why do they matter?+
Core Web Vitals are three metrics Google uses to measure real-world user experience: LCP (Largest Contentful Paint) measures loading speed, INP (Interaction to Next Paint) measures responsiveness, and CLS (Cumulative Layout Shift) measures visual stability. They matter because Google uses them as ranking signals, and they directly correlate with user satisfaction and conversion rates.

Complete Guide to Website Speed Optimization

Website speed optimization is the process of making your web pages load faster and respond more quickly to user interactions. Here's a comprehensive approach to achieving optimal performance.

1. Measure Before You Optimize

Before making changes, establish a baseline. Use Google PageSpeed Insights for Core Web Vitals data, Chrome DevTools for network analysis, and WebPageTest for waterfall charts. Our analyzer gives you a starting point based on your configuration, but real-world testing with your actual URL provides the most accurate picture. Focus on the metrics that matter most: LCP, INP, and CLS.

2. Prioritize by Impact

Not all optimizations are equal. Image optimization typically has the highest impact (30-50% page weight reduction), followed by third-party script management (removing 200-500KB of JavaScript) and server/hosting improvements (reducing TTFB from 800ms to under 100ms). Start with quick wins that require minimal effort but deliver significant improvements.

3. Framework-Specific Strategies

Every framework has unique optimization opportunities. WordPress sites benefit most from caching plugins and lightweight themes. React/Next.js sites should leverage Server Components and ISR. Shopify stores should audit apps and use the built-in CDN. Squarespace sites should minimize custom code injections. Understanding your framework's performance characteristics is key to efficient optimization.

4. Monitor and Maintain

Performance is not a one-time fix. As you add features, install plugins, and update content, performance can degrade. Set up automated monitoring with tools like Lighthouse CI or SpeedCurve. Establish performance budgets (e.g., total page weight under 1MB, LCP under 2.5s) and block deployments that exceed them. Regular audits every quarter help maintain optimal speed.

常见问题

好的速度评分是多少？+
Lighthouse 90以上为良好，70-89有改进空间，70以下需紧急处理。
页面速度影响SEO吗？+
是的。Google将Core Web Vitals作为SEO排名因素。
什么是Core Web Vitals？+
Google定义的网页用户体验指标：LCP（加载速度）、FID（交互性）、CLS（视觉稳定性）。
为什么移动和桌面结果不同？+
移动设备处理能力和网络速度有限，通常比桌面慢。Google优先考虑移动端结果。
如何改善加载时间？+
优化图片、精简JavaScript、利用缓存、使用CDN、迁移到快速托管。
What is the most important Core Web Vital?+
LCP (Largest Contentful Paint) is generally considered the most impactful because it directly measures perceived loading speed. If your LCP is over 4 seconds, users perceive the page as slow regardless of other metrics. However, all three Core Web Vitals (LCP, INP, CLS) need to pass their thresholds for a page to have 'good' Page Experience.
How do I reduce my website's load time by 50%?+
The fastest path to 50% improvement: (1) Optimize images — convert to WebP, add lazy loading, use responsive sizes (saves 30-50% of page weight). (2) Defer third-party scripts — load analytics, chat widgets, and ad pixels after user interaction (saves 200-500KB). (3) Enable CDN — serve assets from edge locations near users (reduces latency 50-80%). These three changes alone typically achieve a 50%+ improvement.
Should I use lazy loading for all images?+
No. Lazy-load images below the fold (not visible on initial viewport) but eagerly load your hero image and any images in the first viewport. Lazy-loading above-the-fold images actually hurts LCP because the browser delays loading the largest visible element. Use loading='lazy' for below-fold images and loading='eager' (or no attribute) for above-fold images.
How do third-party scripts affect performance?+
Third-party scripts (analytics, chat widgets, ad pixels, social embeds) are one of the biggest performance killers. They add 200-500KB+ of JavaScript, block the main thread, and make additional network requests. Google Analytics alone adds ~45KB and 2-3 network requests. The solution: defer non-critical scripts, load them after user interaction, or use lighter alternatives (Plausible instead of GA, for example).
What is the difference between page speed and site speed?+
Page speed measures how fast a specific page loads (measured by metrics like LCP, TTFB, and fully loaded time). Site speed is the average performance across all pages of your website. Google evaluates both, but page speed at the individual URL level matters most for rankings. A fast homepage doesn't help if your product pages are slow. Optimize your most-visited pages first.

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免费网站速度测试 | 网站性能测量 | Kleap