Rank Math vs SEOPress vs AIOSEO: Which Free SEO Plugin Wins in 2026?

There is no clear winner between Rank Math and AIOSEO: on their WordPress.org record they score 94.2 and 94.0 out of 100, a 0.2-point gap that is too small to call. SEOPress trails on 87.9, mostly because it has fewer installs, yet it was level with Rank Math as the lightest in our lab. What separates them is lab overhead and what each free version includes.

In our lab Rank Math (+4.4 ms) and SEOPress (+8.8 ms) were level on server time. AIOSEO added +29.9 ms, the slowest in all three runs: a real gap, and still a small one.

Short answer: Pick Rank Math if you want redirects, a 404 monitor and schema types listed in the free plugin. Pick SEOPress if you want unlimited target keywords in the free version and a free/PRO split spelled out on its page; it is level with Rank Math on server time. Pick AIOSEO if a well-answered support forum matters most to you (26 of 27 recent threads resolved) and you are happy to confirm after install which of its listed features the free version includes, and can accept the most server time of the three.

Last updated: 14 October 2026. We re-run the numbers every month.

Side by side

Yoast SEO is in the last column for reference only; it is not one of the three contenders.

Measure	Rank Math	AIOSEO	SEOPress	Yoast SEO (ref.)
WordPress.org score /100	94.2	94.0	87.9	94.3
Satisfaction /35	31.5	29.7	31.2	31.5
Adoption /25	25	25	20.6	25
Maintenance /20	20	20	20	20
Support /20	17.8	19.3	16.0	17.8
Active installs	4M+	2M+	300,000+	10M+
Rating	96% (7,514 ratings)	94% (5,221 ratings)	96% (1,265 ratings)	96% (27,819 ratings)
Last updated	6 October 2026	7 October 2026	1 October 2026	13 October 2026
Support threads resolved (last 2 months)	40 of 45	26 of 27	4 of 5	32 of 36
Weight added (lab)	+0.0 KB	+1.0 KB	+0.4 KB	+1.1 KB
Server time added (lab, median of 3 runs)	+4.4 ms	+29.9 ms	+8.8 ms	+13.8 ms
Version tested	1.0.280	5.0.3	10.3	28.7
Requires PHP	7.4	7.4	7.4	7.4

How we scored them

The final score is the WordPress.org score we use for every plugin list. Weights out of 100:

• Satisfaction, 35: the star rating, blended with 25 imaginary votes at 80% so a handful of reviews cannot dominate.
• Adoption, 25: active installs on a log scale, 1,000 = 0 and 1,000,000 = full marks.
• Maintenance, 20: updated in the last 30 days earns full marks, sliding to 0 at 365 days.
• Support, 20: the share of the last two months’ support threads marked resolved.

Lab numbers sit beside the score, not inside it. Our lab is WordPress 7.1.3 on PHP 8.5 with Twenty Twenty-Five, serving a 1,500-word post with 3 images to a logged-out visitor. Each plugin was installed on 14 October 2026 and activated alone with default settings. The full method is on how we rank.

Satisfaction: Rank Math and SEOPress edge it

Rank Math and SEOPress both hold a 96% rating, from 7,514 and 1,265 ratings. AIOSEO is at 94% from 5,221 ratings. After blending, that gives Rank Math 31.5 of 35, SEOPress 31.2 and AIOSEO 29.7.

A 1.8-point lead on satisfaction is Rank Math’s largest advantage over AIOSEO anywhere in the score. It is also the reason the two end up level, because AIOSEO wins back almost the same amount on support.

Adoption: SEOPress is the smaller plugin

Rank Math has 4M+ active installs and AIOSEO 2M+. Both are past the 1,000,000 mark where our scale gives full marks, so each takes 25 of 25. SEOPress has 300,000+ installs, worth 20.6.

That 4.4-point gap is most of the distance between SEOPress and the other two. It measures how many sites run the plugin, not how well it works.

Maintenance: a tie

All three were updated within two weeks of our check. SEOPress shipped on 1 October 2026, Rank Math on 6 October and AIOSEO on 7 October. Each takes the full 20 points, and each lists WordPress 7.1.3 as tested.

Support: AIOSEO resolves the most

In the last two months, AIOSEO marked 26 of 27 support threads resolved, worth 19.3 of 20. Rank Math resolved 40 of 45 for 17.8. SEOPress resolved 4 of 5 for 16.0.

Read the SEOPress figure with care: five threads is a small sample, and one unresolved thread costs it 4 points of the 20.

Lab: weight and server time

No plugin here makes your pages meaningfully heavier. On our test post, which weighs 19.8 KB with no plugin, Rank Math added +0.0 KB, SEOPress +0.4 KB and AIOSEO +1.0 KB. None of them added a CSS or JS file to the page.

Server time varies between runs on a shared machine, so we ran each plugin three times and report the median; page weight barely changed between runs (0.1 KB at most). The no-plugin baseline itself ranged from 61 to 80 ms across runs, which is why we compare the time each plugin adds rather than the total.

Rank Math added +4.4 ms and SEOPress +8.8 ms. Gaps under about 10 ms are within the noise of our test, so those two are level. AIOSEO added +29.9 ms, 25.5 ms more than Rank Math and 21.1 ms more than SEOPress, and it was the slowest of the three in all three runs. That gap is real, and still small at about 0.03 seconds per uncached page view.

Rank Math’s own page calls it the “Fastest SEO plugin with barely any impact on site speed”. In our lab it added nothing to page weight and was level with SEOPress on server time.

What each one does (free version)

This section comes from each plugin’s WordPress.org page. All three have paid upgrades, and the pages draw the free/paid line very differently.

Rank Math SEO

Rank Math SEO – AI SEO Tools to Dominate SEO Rankings lists its main features separately from a “Unique Features of Rank Math PRO” section. The main list includes:

• A setup wizard that configures the plugin for your site, with a one-click importer.
• 16+ schema types for rich results.
• Optimization for up to 5 focus keywords per post by default (unlimited with a filter).
• Google Search Console and Google Analytics integration.
• An XML sitemap with custom post type support, SEO breadcrumbs and 30+ one-click SEO tests.
• A redirection manager, a built-in 404 monitor and a role manager.
• One-click import from Yoast, AIOSEO and SEOPress.

Its PRO section lists rank tracking, an advanced schema builder, bulk CSV import of SEO meta and extra WooCommerce schema. The page also says the Content AI features are only active with a connected Rank Math account.

SEOPress

SEOPress – AI SEO Plugin & On-site SEO has a “SEOPress Free Features” list and a separate PRO list, which makes it the easiest of the three to check. The free list includes:

• An installation wizard and an SEO metabox that works across the block editor and page builders.
• Content analysis with unlimited target keywords.
• Google search and social previews, titles and meta descriptions with dynamic variables, Open Graph and X Cards.
• XML sitemaps (including images), an HTML sitemap, and custom canonical URLs and meta robots.
• Redirections at the post, page and custom post type level.
• llms.txt support, Google Analytics 4, Matomo and Microsoft Clarity integration.
• Google Indexing API and IndexNow, plus one-click migration from Yoast, Rank Math and AIOSEO.

Its PRO list includes the redirect manager, 404 monitoring, the broken link checker, the schema editor, breadcrumbs, local SEO and WooCommerce SEO. The page describes the plugin as having “no upsells in admin”.

All in One SEO (AIOSEO)

All in One SEO describes itself as “the lite version of the All in One SEO Pro plugin”. Its feature list does not mark which items are in the free version and which need Pro. Items on that list include:

• An SEO setup wizard and TruSEO on-page analysis for unlimited focus keywords.
• XML sitemaps, a robots.txt editor, canonical URLs and Open Graph social previews.
• Google Search Console data in the dashboard and IndexNow for Bing and Yandex.
• A redirection manager, local SEO, keyword rank tracking and a link assistant.
• An importer from Yoast SEO, Rank Math and SEOPress.

Install it and check which of these appear before you plan around one.

Rank Math vs SEOPress

On the record, Rank Math leads 94.2 to 87.9. Ratings are level (96% each), both are fresh, and the gap comes from installs (4M+ against 300,000+) and support (40 of 45 resolved against 4 of 5). In the lab they are level: +0.0 KB and +4.4 ms for Rank Math against +0.4 KB and +8.8 ms for SEOPress, a gap within our noise.

In a Rank Math vs SEOPress choice, the free feature lists decide more than the score. Rank Math’s main list includes a redirection manager, a 404 monitor and 16+ schema types; SEOPress lists its redirect manager, 404 monitoring and schema editor under PRO. SEOPress’s free version allows unlimited target keywords; Rank Math’s defaults to 5 per post.

Rank Math vs AIOSEO

This is a tie: 94.2 against 94.0. Rank Math has the better rating (96% from 7,514 ratings against 94% from 5,221). AIOSEO has the better support record (26 of 27 threads resolved against 40 of 45).

For Rank Math vs AIOSEO, the lab favours Rank Math: +0.0 KB and +4.4 ms against +1.0 KB and +29.9 ms. The 25.5 ms server-time difference held in all three runs, so it is real, though small. The other difference is the page: Rank Math separates its free and PRO features, and AIOSEO does not.

SEOPress vs AIOSEO

AIOSEO scores 94.0 to SEOPress’s 87.9, on more installs (2M+ against 300,000+) and better support. SEOPress has the higher rating, 96% against 94%. In the lab SEOPress added 21.1 ms less server time, a gap that held in all three runs.

Which should you pick

• A new blog that wants redirects and schema without paying: Rank Math. Its main feature list includes both, plus a 404 monitor.
• A site where every millisecond of server time counts: Rank Math or SEOPress, level at +4.4 and +8.8 ms; AIOSEO added +29.9 ms. With a page cache, these gaps matter much less.
• Writers who target many keywords per post: SEOPress, whose free list includes unlimited target keywords. AIOSEO lists unlimited focus keywords without saying whether that is in the free version, and Rank Math defaults to 5.
• You value a fast-answered support forum: AIOSEO, with 26 of 27 recent threads resolved.
• Moving from another SEO plugin: any of the three. Each lists an importer for the other two and for Yoast.
• You are already on Yoast SEO and it works: at 94.3 on the same record, the numbers give no reason to switch.

Questions people ask

Is Rank Math better than AIOSEO?

Not on our data. Rank Math scores 94.2 and AIOSEO 94.0, a 0.2-point gap. Rank Math has the better rating and AIOSEO the better support record. In our lab Rank Math added 25.5 ms less server time, a small but consistent gap.

Why does SEOPress score lower if it is so light?

Our score is built from the WordPress.org record, and SEOPress has 300,000+ installs against millions for the others. That costs it 4.4 points on adoption. Lab numbers are not part of the score.

Will any of these slow my site down?

Barely. On our test post they added between +0.0 KB and +1.0 KB and no extra CSS or JS files. Median server time rose by +4.4 ms (Rank Math), +8.8 ms (SEOPress) and +29.9 ms (AIOSEO), on a page that took 61–80 ms to build with no plugin.

Can I switch between them later?

Yes. Rank Math lists one-click import from Yoast, AIOSEO and SEOPress; SEOPress lists migration from Yoast, Rank Math and AIOSEO; AIOSEO lists an importer for Yoast SEO, Rank Math and SEOPress.