Free first year = infinite markup: promo domains, dissected
There is a failure mode hiding in every domain price comparison ever built: the renewal-hike percentage. It's the metric that promises to expose the promo trap — how much your bill jumps after year one. But it has a division-by-zero problem at exactly the point where it matters most. When the first year is free (or nearly), the honest answer to "how big is the hike?" is not zero and it is not some large number — it is infinite. And the way most sites compute it, infinity comes out looking like 0%.
How the math breaks
The standard formula is (renewal − year-1) ÷ year-1. When year one costs $9.19 and year two costs $13.55, that's +47% — meaningful. When year one costs $0, the denominator vanishes. Most implementations either crash, skip the row, or — worst and most common — initialize the percentage to 0 and never update it. The result: a registrar offering $0-first-year-then-$23.05 displays as having no markup at all. The single most predatory pricing shape on the internet gets rendered as the cleanest.
What the promos actually look like
| Registrar | TLD | Year 1 | Renewal | Jump |
|---|---|---|---|---|
| IONOS | .store | $1.00 | $79.50 | +7850% |
| IONOS | .online | $1.00 | $62.50 | +6150% |
| IONOS | .site | $1.00 | $57.40 | +5640% |
| IONOS | .com | $1.00 | $20.00 | +1900% |
| GoDaddy | .store | $5.20 | $90.50 | +1640% |
| OVHcloud | .store | €2.98 | €49.50 | +1561% |
| Namecheap | .store | $3.82 | $61.95 | +1522% |
| Spaceship | .store | $3.35 | $50.90 | +1419% |
Look at what unifies that table: everyone is racing to renewals in the $20–$90 range from different depths of loss-leader. The .store first-year prices range from $1.00 to $5.20 across registrars — while every one of them lands on a steep ongoing price set at or near registry rates. That is the signature of a promo war: the discount competes for your checkout click, and the renewal pays for it. None of these numbers are secret; they're just never shown next to each other, because showing them next to each other kills the promo's magic.
Ten-year totals are the antidote
Percentage hikes get absurd as the entry price approaches zero, which is why we recommend ignoring them entirely in favor of the number they were trying to approximate: total cost of ownership over the period you'll actually hold the domain. A $1 IONOS .store held ten years costs $716.50 ($1 + 9 × $79.50). The same TLD at a flat-price registrar with no promo at all would need a renewal under $71.65 just to break even against that headline deal — and most flat registrars' renewals beat it, because flat-pricers don't fund giveaways from the back end. Ten-year math folds the entire promo war into one comparable number, which is why our tool ranks by it by default and treats "ongoing $/yr" as the alternative view.
- If a comparison site shows a 0% hike next to a $0 first-year offer, its math is broken — treat every number on that page with suspicion.
- Infinity is the honest percentage for a free first year; we render it explicitly rather than rounding evil into innocence.
- Promo depth tells you about marketing budgets, not value: the deeper the first-year discount, the higher the true ongoing cost tends to be.
- Always compute your holding-period total before checkout: 1-year thinking is exactly what the promo is optimized for.
Every row cited here is captured data with a timestamp, not a scraped marketing claim — and the interactive version lets you flip between ten-year totals and per-year renewal rates so you can watch the promo war collapse into a plain ranking.