If you self-host video on your own website (rather than using YouTube or TikTok), CDN egress costs can grow faster than expected — especially during traffic spikes or when a video goes viral. practical strategies to optimise egress costs without reducing viewing quality.
What is egress cost?
Egress cost (outbound data transfer fee) is what your CDN charges when your video is delivered from a server to a viewer. Every video view generates a corresponding amount of egress data. With video, these numbers accumulate quickly.
Simple example: 10,000 views of a 720p 5-minute video ≈ approximately 5–10 GB egress depending on codec and bitrate — roughly $0.05–$0.50 on Bunny.net, higher on CloudFront Asia Pacific. These are estimates — verify with your actual provider.
Strategy 1 — Use adaptive bitrate (ABR)
Instead of always streaming at the highest quality, ABR dynamically adjusts bitrate to match the viewer's network speed. A viewer on a slow connection gets 480p instead of 1080p — significantly reducing egress while they barely notice the difference. Cloudflare Stream and Mux both have good ABR support.
Strategy 2 — Optimise your codec
Use more efficient codecs (H.265/HEVC or AV1) instead of older H.264. Same visual quality but 30–50% smaller file size = proportionally lower egress. Note: H.265 and AV1 require additional encoding and may not be compatible with older browsers — test thoroughly before deploying.
Strategy 3 — Geo-restrict if your audience is concentrated
If most of your audience is in Vietnam, consider using a CDN provider with Vietnamese nodes (ViettelIDC, VNPT Cloud) instead of a global CDN — domestic egress is typically cheaper than international egress. However, if your audience is spread across regions, this strategy may increase latency for distant viewers.
Strategy 4 — Cache aggressively
- Set long cache TTLs for video files (video does not change after upload)
- Use immutable cache headers for video files
- Avoid unnecessary cache-busting — every cache bust forces CDN to re-fetch from origin
Strategy 5 — Lazy load with thumbnail first
Do not auto-play video on page load — show only the thumbnail. The video is only fetched when the user clicks play. This significantly reduces egress from users who browse the page but do not actually watch the video.
Monitor egress in real time
Most CDN providers have analytics dashboards — set alerts when egress exceeds a threshold to avoid bill shock. Bunny.net, Cloudflare, and AWS CloudFront all offer this capability.
See also: CDN cost benchmark for Vietnam providers, Video CDN GeoIP routing for Vietnam creators.
Download and store videos from any platform via Klypio or @KlypioBot. See also: YouTube downloader, Vimeo downloader.