I Bought a Domain That Used to Sell Viagra. Here's My SEO Recovery Log.

#seo #equation #solver #math

I Bought a Domain That Used to Sell Viagra. Now It Teaches Math.

I have loved math since I was a kid. Not the performative kind of love —
the real kind, where you solve a problem at midnight and feel genuinely
better about the world. Algebra made sense to me before poetry did.
Systems of equations felt like detective work. Derivatives, when they
finally clicked, felt like someone had handed me a key to every
changing quantity in the universe.

Years later, I wanted to build a thing I wished existed when I was
fifteen: a free, honest, step-by-step math solver that treats students
like curious humans instead of ad impressions. No paywall at step
three. No "upgrade to see the answer." No signup to solve a linear
equation.

That project became equation-solver.org.

This is the story of how I almost buried it under a decade of SEO
ghosts — and how the site eventually became what I wanted it to be.

The domain that wasn't clean

I found the name in a drop auction. Ten years old, brandable, the
letters spelled exactly what I was building. I clicked buy for the
price of a coffee and felt clever.

A few weeks after launch, Google Search Console lit up. Impressions.
Thousands of them. I was thrilled for roughly ninety seconds, until I
read the queries.

They were in Russian. In Ukrainian. In Spanish. And they were not
about math.

They were about pharmacies. Cialis without prescription. Generic
Viagra online. Canadian pharmacy no RX. The landing pages in the
report were URLs that had never existed on my site — long pharma
permalinks Google was still associating with the domain after a
decade.

I opened the Wayback Machine. Year after year of snapshots showed the
same templated online-pharmacy landing pages, cloned across a dozen
language stubs. My clean new math site was renting a house that
used to be a crack den, and the neighborhood remembered.

The SEO recovery, honestly

I am not going to pretend I fixed it in a week. Here is what actually
happened, in rough order:

I audited everything. Ahrefs showed thousands of toxic referring
domains, almost all of them low-quality link farms with pharma anchor
text. I tagged every one of them.

I filed a disavow. A disavow.txt with thousands of domain
entries, submitted through Search Console. This is Google's "please
ignore these links" button and it is slow — not magic. It took
several crawl cycles before pharma impressions started fading.

I rebuilt from zero. No rescue of old URLs, no 301 gymnastics.
Just a clean new site, built in nine languages from day one —
English, Turkish, German, Spanish, French, Italian, Japanese,
Chinese, Portuguese. Nearly five hundred pages, all interlinked,
all with proper hreflang, all with structured data. If the domain
was going to earn trust back, it was going to earn it honestly.

I waited. This is the part every SEO blog skips. Recovery is not
a hockey stick. It is months of quietly watching the graph climb
while your competitors, on clean domains, outrank you for queries
you should own.

The pharma impressions are essentially zero now. The site ranks for
a growing set of real math queries. There is still a ceiling — I
can feel it — but the ghost is much quieter than it was.

Lesson in one sentence: domain history is not a line item, it is
a shadow. Aged-domain marketplaces sell you the age and do not
mention the cause of death. Always open Wayback before you click buy.

What the site actually does (the part I like writing)

With the SEO drama mostly behind me, I get to talk about the thing
itself. The site is a free step-by-step equation solver that covers most of what a student sees
from middle school through early university.

Here is what lives inside it:

Linear equations, solved line by line — type something like
0.2x + 0.5(100 - x) = 0.3 * 100 and watch the solver expand,
collect, isolate, and verify. Every intermediate form is shown,
not hidden behind a paywall.
Systems of equations. Substitution and elimination, both
methods, step by step. If your teacher insists on showing work,
so do we.
Quadratic equations with full derivation. Discriminant,
factoring when it factors, the quadratic formula when it doesn't,
and a verification line at the end so you know the answer is right.
Word problems in plain language. Age problems, mixture problems,
rate-time-distance, work problems — the classic pain points of
middle-school math, converted automatically into equations and
solved with the same step-by-step honesty as the symbolic solver.
A derivative calculator that shows the rule it applied at each
step (power rule, chain rule, product rule) instead of just
spitting out a final expression.
Interactive solving. Paste an equation into the URL as a
parameter and the site animates the solution on load — great for
sharing a solved problem to a classmate or embedding in a lesson.
Nine languages. If you speak Turkish, the
same site in Turkish is not a
Google Translate overlay. It's a native build with translated UI,
translated lessons, translated URL slugs, and locale-aware number
formatting. Same for the other eight.
No signup. No ads. No freemium wall. The entire solver runs
client-side in pure JavaScript. Your equations never leave your
browser. The site is fully static, served from the edge, and
free forever.

If any of that sounds useful to you or to a student you know,
equation-solver.org is the link.
Throw any equation at it. If it fails on something it should handle,
tell me in the comments and I will fix it.

What's next

I am undecided on whether to migrate to a cleaner domain or keep
fighting the SEO ceiling on this one. There is no clean answer.
What I am sure of is that the math part — the thing I actually
cared about from the start — is finally bigger than the domain's
past.

If you, too, loved math before it got turned into standardized
testing fuel, I think you'll enjoy poking at the solver. And if
you are about to buy an aged domain for your own project: please,
open Wayback first.

If you have recovered a domain from a worse history than this, I
want to hear the playbook. Drop it in the comments.