Netlify's 100GB bandwidth cap: what happens when you exceed it
Key Facts
Direct answer: The direct answer is that when you exceed Netlify's 100GB monthly bandwidth cap on the free tier, your site will become inaccessible to visitors until the next billing cycle begins, effectively going offline for the remainder of the month.
What the bandwidth cap actually means: Netlify's bandwidth cap refers to the total amount of data transferred from your site's servers to visitors over a monthly period.
When you'll hit it: You're most likely to encounter Netlify's bandwidth cap when your site experiences unexpected traffic spikes or serves large media files.
How to verify if it applies to you: To check your current bandwidth usage in Netlify, navigate to your site's dashboard in the Netlify web interface.
For developers and businesses relying on Netlify to host their static sites and applications, the platform's generous free tier has long been an attractive option. However, this free tier comes with limitations, most notably a 100GB monthly bandwidth cap. As your site grows in popularity or serves more media-rich content, this cap can become a significant constraint, potentially disrupting your service and user experience.
The direct answer is that when you exceed Netlify's 100GB monthly bandwidth cap on the free tier, your site will become inaccessible to visitors until the next billing cycle begins, effectively going offline for the remainder of the month. Netlify displays a prominent bandwidth exceeded message on your site, and while you still have access to the dashboard to upgrade your plan or monitor usage, your published site returns a 502 Bad Gateway error to all incoming traffic.
What the bandwidth cap actually means
Netlify's bandwidth cap refers to the total amount of data transferred from your site's servers to visitors over a monthly period. This includes all HTTP requests, image loads, CSS and JavaScript files, API responses, and any other assets served by your site. The 100GB limit is calculated as the sum of all outgoing traffic from your site's domains and functions. When you approach this limit, Netlify begins showing warnings in your dashboard, typically when you've used 80% of your allocation. Once you exceed the 100GB threshold, Netlify stops serving your site content to prevent additional costs, though the site remains available in your dashboard for management purposes. This mechanism is designed to prevent unexpected charges while ensuring fair resource allocation among free tier users.
The bandwidth calculation includes both successful requests and error responses, meaning that even if your site is experiencing issues generating 502 errors, those responses still count toward your bandwidth cap. Additionally, Netlify's bandwidth measurement includes traffic from all associated domains, subdomains, and any serverless functions associated with your site. This comprehensive approach means that a single popular blog post, a viral marketing campaign, or an unexpectedly popular API endpoint can quickly consume your monthly allocation, even if your typical usage is much lower.
When you'll hit it
You're most likely to encounter Netlify's bandwidth cap when your site experiences unexpected traffic spikes or serves large media files. For instance, if you run a photography blog with high-resolution images, a single popular post with 10MB images viewed by 10,000 visitors would consume approximately 100GB of bandwidth in one day. Similarly, if your site becomes the subject of social media attention or is featured in a newsletter, the resulting traffic surge could exhaust your monthly allocation in just a few hours. E-commerce sites, especially those during sales events, and portfolio sites showcasing large design files or video content are particularly vulnerable to hitting this limit.
The cap can also be reached gradually through consistent but substantial traffic. A site with 50,000 monthly visitors viewing an average of 2MB of content per session would consume approximately 100GB over the course of a month. Many developers don't realize how quickly bandwidth adds up when serving modern web applications with numerous assets, third-party scripts, and API calls. Even sites that appear lightweight can exceed the cap if they have high traffic volumes or serve content to international audiences with multiple page views per session.
How to verify if it applies to you
To check your current bandwidth usage in Netlify, navigate to your site's dashboard in the Netlify web interface. In the left sidebar, click on "Site settings" and then select "Build & deploy." Scroll down to the "Analytics" section where you'll find your current bandwidth usage displayed alongside your monthly limit. Netlify provides a real-time graph showing your usage throughout the current billing period, making it easy to identify trends and potential spikes. You can also set up usage alerts to receive email notifications when you approach your limit, typically at 80% and 95% of your allocation.
For more detailed bandwidth analytics, you can use Netlify's analytics platform, which provides breakdowns by URL, visitor location, and device type. This data can help you understand which parts of your site are consuming the most bandwidth. Additionally, if you suspect you've exceeded your cap but can't see the exact usage in the dashboard, your site being inaccessible with a 502 error is a clear indicator. You can also check your Netlify account's billing section to see if any overage charges have been applied, though on the free tier, the primary consequence is site suspension rather than additional fees.
Your options
Upgrade to a paid plan: Move to Netlify's Pro, Team, or Enterprise plans which offer significantly higher bandwidth allowances starting at 200GB per month on the Pro tier, with no hard caps on higher tiers.
Implement a CDN with caching: Add a content delivery network like Cloudflare or AWS CloudFront in front of Netlify to cache static assets and reduce bandwidth consumption from Netlify's servers.
Optimize assets: Compress images, minify CSS and JavaScript files, and implement lazy loading to reduce the average page weight and bandwidth usage.
Deployxa: Consider a platform like Deployxa which offers unlimited bandwidth and scalable resources specifically for AI-built applications without the same restrictive caps as Netlify's free tier.
Common Pitfalls and Troubleshooting
The first pitfall is assuming that small files won't add up to exceed the cap. Many developers focus only on large images or videos while underestimating how quickly bandwidth is consumed by numerous small assets, third-party scripts, and API calls. To fix this, regularly audit your site's assets and use tools like Lighthouse to identify and optimize large or numerous resources that contribute to bandwidth consumption.
The second pitfall is not setting up usage alerts, which means you might only discover you've exceeded your cap after your site has already gone offline. To prevent this, configure bandwidth alerts in your Netlify dashboard and monitor your usage regularly, especially during marketing campaigns or when promoting new content that might drive traffic spikes.
The third pitfall is confusing bandwidth with storage limits. While Netlify's free tier also includes 100GB of build and deploy storage, this is separate from bandwidth and won't directly cause your site to go offline. To avoid confusion, regularly check both metrics in your dashboard and understand that exceeding storage limits might prevent new deployments but won't immediately affect your live site's accessibility.
The fourth pitfall is not accounting for all subdomains and associated sites in your bandwidth calculation. If you have multiple domains or subdomains pointing to the same Netlify site, all traffic from these domains counts toward the same 100GB cap. To address this, consolidate domains where possible and monitor traffic from all associated domains to get an accurate picture of your total bandwidth usage.
The fifth pitfall is assuming that Netlify's free tier includes unlimited bandwidth for serverless functions. Function executions also count toward your bandwidth cap, and complex functions with large payloads can quickly consume significant portions of your allocation. To mitigate this, optimize your functions to return minimal payloads and consider implementing caching strategies to reduce redundant function calls.
Conclusion
Understanding Netlify's 100GB bandwidth cap is essential for any developer relying on the platform for production websites. While the free tier offers an excellent entry point, the bandwidth limitation can create significant risks for growing sites or those serving media-rich content. By monitoring your usage, implementing optimization strategies, and having a plan for exceeding the cap, you can ensure your site remains accessible to visitors without interruption. For applications that require more predictable scaling and unlimited resources, exploring alternative platforms may provide the reliability needed for sustained growth. To learn more about Netlify's bandwidth policies and explore upgrade options, visit Netlify's official documentation and pricing pages.