To cut Cloud CDN and Media CDN cost on GCP, pick the right product for your traffic, raise the cache hit ratio, tune TTLs and cache keys, and keep origin pulls in-region. Cache hit ratio is the dominant lever: every miss pays an origin egress or fill charge and forfeits cheaper edge delivery. Use Media CDN for large-scale video and Cloud CDN for web apps and APIs. Cache egress in North America and Europe is tiered, starting around 0.08 US dollars per GiB and falling with volume, so most of the optimization is moving bytes from origin to a well-tuned cache.
Last updated: June 2026. Written by Fredrik Filipsson and reviewed by Morten Andersen, built on our See, Cut, Lock, Run method.
This guide sits in our complete guide to Google Cloud cost optimization, the cluster pillar it links up to, and connects to the broader cloud cost optimization playbook. CDN cost is closely tied to storage egress, so read it alongside our companion guide on how to reduce Cloud Storage egress and operation costs on GCP. Caching delivery is a Cut step move that lowers both egress and origin load.
Cache hit ratio. Every request that misses the cache pulls from origin, paying a cache fill or origin egress charge and adding origin compute, then still pays to deliver the bytes. Lifting the hit ratio shifts traffic onto cheaper edge egress and cuts the origin side at the same time. Before tuning rates or products, measure your hit ratio per content type; the assets with low ratios and high volume are where the savings are.
What drives Cloud CDN cost on GCP?
Cloud CDN cost is driven mainly by cache egress to users, cache fill from origin, and cache lookup requests. Per the Google Cloud CDN pricing documentation, cache egress in North America and Europe is tiered, beginning around 0.08 US dollars per GiB for the first tier and declining toward 0.02 US dollars per GiB at very high volume, cache fill is charged per GiB pulled from origin, and cache lookups are billed per block of requests. The structure rewards a high hit ratio: when most requests are served from the edge, you pay the cheaper cache egress and avoid fill, but a low ratio means you pay to pull from origin and to deliver. Verify current per-GiB rates for your region in the linked pricing page before modeling, because Google Cloud network prices change.
What is the difference between Cloud CDN and Media CDN?
Cloud CDN is built for web apps, APIs, and image-heavy sites and plugs into the global external load balancer, while Media CDN is built for large-scale video streaming and large file delivery on Google's media-optimized edge. Picking the product that matches your traffic is the first cost decision, because the two are engineered for different shapes of load. A streaming or large-download workload on Cloud CDN leaves throughput and cache efficiency on the table that Media CDN is designed to capture; a dynamic web app does not need Media CDN's media features. Match the product to the dominant traffic type, and split if you run both.
How do I raise the cache hit ratio, step by step?
Raise the hit ratio by caching more, caching longer, and caching more requests to the same object. Five steps:
- Pick the right product. Use Media CDN for video and large files, Cloud CDN for web and API traffic. Result: the edge engineered for your load.
- Set generous TTLs on stable assets. Give static content long time-to-live values so it stays cached. Result: fewer origin pulls per object.
- Normalize cache keys. Strip unnecessary query parameters and headers from the cache key so variants collapse to one cached object. Result: a higher hit ratio on the same content.
- Enable negative caching. Cache error and not-found responses briefly so repeated misses do not hammer origin. Result: lower fill on bad requests.
- Watch fill and request charges. Monitor cache fill and lookup charges next to egress. Result: a true picture of where the CDN spends.
Paying more for your CDN than it saves you?
Our Google Cloud cost audit measures cache hit ratio by content type, picks the right CDN product, tunes TTLs and cache keys, and quantifies the egress and fill you can reclaim. On the performance model, you pay only from realized savings. No savings, no fee.
Book a Google Cloud cost audit →How does the CDN affect overall GCP egress?
A well-tuned CDN reduces overall GCP egress because cache egress is generally cheaper per GiB than standard internet egress, and a high hit ratio keeps most bytes from ever leaving origin. The relationship is conditional: a CDN with a poor hit ratio can cost more than direct delivery, because you pay cache fill plus egress on every miss while still bearing origin egress. Keep origin and cache in the same region to avoid adding internal egress to the fill cost, and treat the CDN as part of the wider egress picture covered in our Cloud Storage egress guide. Tune caching first, and the CDN becomes a net reduction in delivery cost.
The Google Cloud Cost Optimization Field Guide includes the CDN hit-ratio worksheet and the product selection matrix referenced above. It is the downloadable companion to this guide.
Frequently asked questions
What drives Cloud CDN cost on GCP?
Cloud CDN cost is driven mainly by cache egress to users, cache fill from origin, and cache lookup requests. Cache egress is the bytes served from the edge, billed per GiB on a tiered scale that falls with volume; cache fill is the bytes pulled from origin when content is not cached; and lookup requests are billed per block of requests. A low cache hit ratio raises all three, because more requests miss the cache and pull from origin.
What is the difference between Cloud CDN and Media CDN?
Cloud CDN is built for web apps, APIs, and image-heavy sites and integrates with the global external load balancer, while Media CDN is built for large-scale video streaming and large file delivery on Google's media-optimized edge. Media CDN handles high-throughput, long-tail content distribution; Cloud CDN handles dynamic and mixed web traffic. Choosing the product that matches your traffic shape is the first cost decision.
How does cache hit ratio affect the bill?
Cache hit ratio is the single biggest lever, because every cache miss pays both an origin egress or fill charge and forfeits the cheaper edge delivery. Raising the hit ratio shifts bytes from expensive origin pulls to cheaper cache egress and cuts origin compute load at the same time. Tuning TTLs, normalizing cache keys, and enabling negative caching are the standard moves to lift it.
Does a CDN reduce overall GCP egress cost?
Usually yes, because CDN cache egress is generally cheaper per GiB than standard internet egress, and a high hit ratio means most bytes never leave origin. The savings depend on hit ratio: a poorly cached CDN can cost more than serving directly, since you pay fill plus egress on every miss. Tune caching first, then the CDN becomes a net reduction in delivery cost.
The short version
Match Media CDN or Cloud CDN to your traffic, then drive the cache hit ratio up with TTLs, cache key normalization, and negative caching, keeping origin pulls in-region. That turns the CDN into a net reduction in delivery cost rather than an extra line on the bill. When you want the hit ratio measured and the product and caching tuned on your real traffic, that is what our Google Cloud cost optimization service delivers.
Cloud pricing and service behavior change frequently. Verify the specifics in this guide against the providers’ own current documentation and the FinOps Foundation: Google Cloud pricing ↗, Google Cloud documentation ↗ and FinOps Foundation Framework ↗. This article also reflects Cloud Cost Room’s hands-on, vendor-neutral engagement experience.