Slim SEO alternatives: six plugins measured on the same site

If you want to stay as light as Slim SEO, The SEO Framework is the only plugin that beats it on server cost (+8.0 ms and 0 queries against +10.0 ms and 2), and it fixes Slim SEO's lastmod and X tag gaps, though with a smaller sitemap. If you are leaving because you want settings or AI features, Hydrogen SEO and SEOPress are the lightest options with a real dashboard.

Figures come from our seven-plugin benchmark, free versions at defaults on one WordPress 7.1 install. We build Hydrogen SEO, one of the six below.

Why people look for an alternative

Slim SEO is one of the two lightest plugins we measured, so people rarely leave it for speed. The data shows what they do leave for:

  • Very little configuration. It added no admin menu items in our test. That is the design, and it is also the limit: if you want to adjust output, there is little to adjust.
  • Thin X output. Only 2 X tags, the fewest of any plugin, against 5 to 8 for most others.
  • Sitemap freshness. 23 of its 73 sitemap URLs had no lastmod.
  • No AI features. It does not generate titles, descriptions or alt text.

Reasons to stay: it has the smallest package (1.4 MB) and head growth (+1,649 bytes) in the field, autoloaded options fractionally below baseline, no tables, and a clean deactivation. It still printed 10 schema types, 11 Open Graph tags, a meta description, and a 73-URL sitemap with all 40 featured images. For a site that wants SEO handled and never touched, it is hard to beat.

If you do switch, expect a heavier admin: every alternative adds at least two menu items, and all but The SEO Framework load more into the editor. Each plugin also has its own idea of which archives belong in the sitemap, so compare URL counts after the move.

  1. The SEO Framework

    +8 ms front-end, +0 queries, 0 custom tables, 9 JSON-LD types

    Slightly lighter on the server (+8.0 ms, 0 queries, 8 hooks) with the lightest editor we measured (77.6 KB). It stamps lastmod on every sitemap URL and prints 5 X tags. The catch is its sitemap: a flat 51 URLs without archives or images, where Slim SEO includes both. See The SEO Framework vs Slim SEO.

  2. Hydrogen SEO

    +12.9 ms front-end, +1 queries, 0 custom tables, 10 JSON-LD types

    Our plugin. It fixes Slim SEO's two output gaps (full lastmod on 72 URLs, 5 X tags) while keeping images in the sitemap, no tables and a single query. It adds a settings dashboard and AI features. The costs are real: +12.9 ms, +4.5 MB, a 4.6 MB package and a 700.4 KB editor bundle, and it is Beta. See Hydrogen SEO vs Slim SEO.

  3. SEOPress

    +24.5 ms front-end, +1 queries, 1 custom tables, 0 JSON-LD types

    A full, restrained settings interface with 6 X tags and a sitemap that includes images, for +24.5 ms and one query. Its free version printed no schema at defaults, so you would lose the 10 types Slim SEO prints. See SEOPress vs Slim SEO.

  4. Rank Math

    +36.1 ms front-end, +16 queries, 6 custom tables, 6 JSON-LD types

    Every setting you could want and the fullest social tags we measured (8 X tags), plus full lastmod. It costs much more (+36.1 ms, 16 queries, six tables, 1,792 KB editor), prints fewer schema types, and leaves images out of its sitemap by default. See Rank Math vs Slim SEO.

  5. Yoast SEO

    +39 ms front-end, +3 queries, 6 custom tables, 12 JSON-LD types

    The most complete output in the test (12 schema types, 75 sitemap URLs with images, near-full lastmod) and a large ecosystem, at roughly four times Slim SEO's PHP time, six tables and the heaviest editor we measured. It prints no meta description by default. See Yoast vs Slim SEO.

  6. All in One SEO

    +53.5 ms front-end, +22 queries, 9 custom tables, 8 JSON-LD types

    A guided interface with full lastmod, but the heaviest plugin in every cost category we measured, with the largest package and head growth where Slim SEO has the smallest. Choose it only if a guided interface matters more than anything else. See All in One SEO vs Slim SEO.

All seven, measured

MeasuredSlim SEO 4.10.1The SEO Framework 5.1.4Hydrogen SEO 0.0.18SEOPress 10.2Rank Math 1.0.278Yoast SEO 28.4All in One SEO 5.0.1.1
Front-end PHP time added+10 ms+8 ms+12.9 ms+24.5 ms+36.1 ms+39 ms+53.5 ms
Peak memory added+2 MB+2 MB+4.5 MB+6.5 MB+8.5 MB+10.5 MB+14.5 MB
Database queries added+2+0+1+1+16+3+22
Hooks registered+51+8+22+114+155+187+100
<head> bytes added+1,649+3,821+4,259+2,380+4,965+5,656+6,668
Meta description by defaultYesYesYesYesYesNoYes
JSON-LD types printed1091006128
Open Graph / X tags11 / 210 / 510 / 510 / 611 / 810 / 56 / 3
Sitemap URLs listed73517258597573
Sitemap image entries40040400400
lastmod coverage50 / 7351 / 5172 / 7250 / 5859 / 5974 / 7573 / 73
Custom database tables0001669
Autoloaded options added-0.2 KB+4.2 KB+0.4 KB+3.6 KB+11.6 KB+13.6 KB+14.6 KB
Plugin package size1.4 MB2.9 MB4.6 MB11.7 MB15.1 MB21 MB24.4 MB
Block editor assets14 files, 187.7 KB25 files, 77.6 KB2 files, 700.4 KB17 files, 217 KB24 files, 1,792 KB48 files, 4,160 KB130 files, 3,543 KB
After deactivationReleases everythingReleases everything (exact baseline)+0.2 KB left autoloadingNo reduction at all+11.0 KB still autoloading+2.6 KB left autoloading, 6 tables remainNo reduction: 14.5 KB still autoloading

Measured on one WordPress 7.1 install (PHP 8.2, MySQL 8.0, Twenty Twenty-Five, 40 posts), each plugin alone with default settings, against a no-plugin baseline. Bold marks the better number in each row. Full method: how we tested.

Common questions

What is lighter than Slim SEO?

The SEO Framework, on PHP time and queries: +8.0 ms and 0 queries against +10.0 ms and 2. Slim SEO remains smaller on package size and head growth.

Which alternative fixes Slim SEO's lastmod gap?

The SEO Framework, Hydrogen SEO, Rank Math and All in One SEO all stamped lastmod on every sitemap URL. Of those, only Hydrogen SEO also included featured images.

Is there a light alternative with settings?

Hydrogen SEO and SEOPress are the lightest plugins with full settings interfaces in our test, at +12.9 ms and +24.5 ms, each adding one query.