Semrush vs SE Ranking (2026): Free Tier vs Trial

Both of these bill themselves as all-in-one SEO suites — site audit, rank tracking, AI visibility — and both get recommended interchangeably in “best SEO tool” roundups. We ran each against this site’s own live domain, solostacklab.net, and compared what actually happened. Full writeups: Semrush review and SE Ranking review.

One honest caveat up front: we tested different access levels for each. Semrush was tested entirely on its free, no-signup tier (Site Audit, AI Visibility, limited Position Tracking) — we deliberately stayed there rather than starting a paid trial. SE Ranking was tested on its 14-day free trial, which unlocks more than Semrush’s free tier does, including Keyword Research. That difference in what we could access shapes some of what follows, and we’ve flagged it inline rather than pretending it’s an apples-to-apples paid-plan comparison.

Getting started: one needs nothing, one needs a fight

Semrush’s free tier needs no signup and no credit card at all — you can point it at a domain and get results immediately.

SE Ranking’s 14-day trial also needs no credit card, but the signup form demands a “work email” and flatly rejected our business Gmail address ([email protected]) with “Use your work email address ([email protected]) to continue.” We worked around it with a free Cloudflare Email Routing address on our own domain — a real ten-minute detour if you don’t already have one set up. Onboarding also defaulted our country/language/currency to Japan/日本語/JPY, which we had to manually correct to match this site’s actual US/English audience.

If your goal is “run one report right now with zero friction,” Semrush gets you there faster.

Site Audit: the free tool gave more than the trial did

This is the finding that surprised us most, because it runs backwards from what the access-level difference would predict.

Semrush’s completely free Site Audit found a genuine, previously-unknown bug: https://www.solostacklab.net/ had no DNS record at all. Not a redirect, not a 404 — nothing. We confirmed it independently with nslookup and fixed it the same session. The audit told us exactly which URL had the problem.

SE Ranking’s 14-day-trial Site Audit gave us a Health Score (86/100) and issue counts by category (“No inbound links: 6,” “Internal links to 3XX redirect pages: 7”) — informative at a glance. But clicking into the Issue Report to see which specific pages had those errors showed every detail row replaced with “Available by subscription” and an “UNLOCK AUDIT” button. Despite being on an active trial, not the free tier, we got zero actual URLs to act on.

Both tools also paywall something: Semrush locks Core Web Vitals behind a paid plan even on its free tier. But for the core “here’s what’s actually broken and where” job, Semrush’s free audit was more useful than SE Ranking’s trial audit, in our own test.

Keyword Research: only tested on one side

SE Ranking’s Keyword Research was the strongest single feature we found in either tool: searching “programmatic seo” returned a Difficulty score (40/100), monthly volume (590), CPC ($3.12), and the actual ranking URLs — specific pages from Reddit, Semrush’s own blog, Zapier, and HubSpot. That’s concrete, usable competitive research.

We can’t make the same claim for Semrush one way or the other — keyword research sits behind a paid plan we didn’t test, since this review stayed in the free tier on purpose. If keyword research is your primary use case, SE Ranking’s trial gives you a real, verified look at that data today; Semrush’s equivalent is untested by us as of this writing.

AI visibility tracking: same 0%, same kind of misleading dashboard tile

Both tools track whether AI answer engines (ChatGPT, Gemini, AI Overviews) cite your domain, and both showed 0% presence for solostacklab.net — a useful cross-tool confirmation rather than a one-off number, later also confirmed by NEURONwriter and our own manual ChatGPT check.

Both dashboards also each have their own easy-to-misread stat sitting right next to the real number:

• SE Ranking displays “Sources Presence: 100%” next to the 0% mention/link figures — read quickly, it looks like a visibility win. It isn’t: it means 100% of AI answers had source links to something, not that any source was us.
• Semrush’s Position Tracking widget shows “100% visibility, position 1” for the keyword solostacklab.net — true of nearly every domain for a search of its own name, not a real ranking achievement, despite the confident framing.

Neither tool is lying, but both need a second look before you screenshot a big percentage as a win.

Which should you use?

• Start with Semrush if you want a genuine, zero-cost technical health check with no signup — in our test it found a real, specific bug that a paywalled trial from a competing tool didn’t surface any equivalent detail for.
• Use SE Ranking’s trial if keyword research is what you actually need right now — its data was specific and immediately usable — but budget time for the Gmail-signup workaround, and don’t expect the Site Audit’s page-level findings without upgrading.

For our own site, that currently means Semrush for the recurring free technical check, and SE Ranking kept around for keyword research specifically — not a single winner, two different jobs.