Site speed and EPC are linked through one direct chain: a faster time-to-first-byte (TTFB) shortens total page load, a shorter page load raises the share of clicked visitors who actually convert, and a higher conversion rate multiplies straight through to your earnings-per-click (EPC) for any fixed commission. A speed improvement never adds a flat euro amount to your payout on its own - it compounds through conversion rate first, the same way every other lever in the funnel does. The worked example below reuses the exact visitor, CTR, and commission numbers from the homepage's Affiliate Earnings Simulator, with one variable made explicit: how conversion rate reacts to load time.
The chain, in order
Four links, each one feeding the next:
- TTFB (time to first byte). How long the server takes to start sending the response, before any HTML has even reached the browser. This is entirely a hosting and application problem - caching, database queries, PHP process availability - and nothing the visitor's device or connection can fix.
- Full page load. TTFB plus everything after: HTML parsing, CSS, images, and - on affiliate landers specifically - every tracking pixel, ad-network script, and redirect chain you've bolted on. This is where a fast server can still ship a slow page.
- Conversion rate. The share of visitors who click through and actually convert. Impatient, already-clicked ad traffic is exactly the audience most likely to abandon a slow page before it ever sees your offer.
- EPC. Using the same formula as the homepage simulator: EPC = conversion rate × commission × months retained (or ×1 for a one-off commission). Conversion rate is the only link in that formula that speed can move - so speed's entire effect on EPC runs through it.
A worked example, with the assumption stated plainly
Start from the homepage simulator's own default scenario: 22,000 monthly visitors, a 3.8% click-through rate, a €22 recurring commission retained for 5 months on average. At the simulator's baseline 1.1% conversion rate, that's 836 clicks, roughly 9 sales, and a €1,012/month payout at an EPC of €1.21 - the same numbers the tool shows by default.
Now hold everything constant except load time, and apply an illustrative conversion-rate index to show the direction and rough scale of the effect - this index is a labeled assumption for this example only, not a measured statistic from any specific study or network:
| Load scenario | Illustrative TTFB | Conversion rate applied | Sales/mo | Revenue/mo | EPC |
|---|---|---|---|---|---|
| Fast | ~150ms | 1.10% | 9 | €1,012 | €1.21 |
| Typical | ~450ms | 0.88% | 7 | €809 | €0.97 |
| Slow | ~900ms+ | 0.61% | 5 | €556 | €0.67 |
The conversion-rate figures in the "typical" and "slow" rows apply a -20% and -45% relative index to the fast-scenario baseline purely to illustrate how a slowdown compounds through the funnel - they are not pulled from a specific measured study, and your own mileage will vary by niche, traffic source, and audience patience. Swap your own numbers into the Affiliate Earnings Simulator to see the effect on your actual funnel.
The pattern that matters isn't the exact percentages - it's that going from "fast" to "slow" here cuts revenue by roughly 45% while nothing about traffic, CTR, or commission changed. That's the entire argument for treating TTFB as a revenue lever, not a vanity metric.
What TTFB should a lander have?
Aim for well under 200 milliseconds of server response time on modern NVMe-backed, HTTP/3 hosting - that's achievable for a typical affiliate lander before any client-side rendering even begins. Past roughly 600-800 milliseconds of TTFB, impatient ad-click traffic increasingly starts leaving before the page has painted anything at all, which is the "slow" row in the table above.
Does Core Web Vitals affect affiliate SEO?
Only modestly, and mostly as a tie-breaker. Google has been explicit in its own public documentation that page-experience signals like Core Web Vitals (LCP, INP, CLS) are a minor ranking factor next to content relevance and links - a fast page doesn't out-rank a better-matched slow one. For affiliate landers specifically, speed matters more through two other channels that have nothing to do with organic rank: paid ad platforms fold landing-page speed into Quality Score and cost-per-click, so a slow lander pays more per click before your EPC math even starts, and a slow page loses conversions regardless of where it sits in search results. Treat Core Web Vitals as a cost-per-click and conversion lever first, and an SEO lever a distant second.
The cheapest speed win
Fix server-side TTFB first - caching, opcode caching, and avoiding a bloated per-lander plugin stack - because every other millisecond on the page stacks on top of that floor; no amount of front-end polish fixes a slow server. The next cheapest win is trimming render-blocking third-party tracking-pixel and ad-network scripts down to only what each specific lander actually needs. On affiliate pages those pixels are frequently the single biggest blocking-resource cost on the page, bigger than your own content - and unlike server hardware, cutting a script you don't need costs nothing.