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.
The SEO Framework
Measured on 5.1.4: +8 ms front-end, +0 queries, 9 JSON-LD types, 0 custom tables
Slightly lighter on the server (+8.0 ms, 0 queries, 8 hooks) with the lightest editor we measured (77.6 KB). It stamps
lastmodon 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.Hydrogen SEO
Measured on 0.0.18: +12.9 ms front-end, +1 queries, 10 JSON-LD types, custom tables in 0.0.31: 1 (2 with the 404 Monitor on)
Our plugin. It fixes Slim SEO's two output gaps (full
lastmodon 72 URLs, 5 X tags) while keeping images in the sitemap and a single query. It had no tables when benchmarked at 0.0.18; in 0.0.31 link counts live in one table and the 404 Monitor, when used, logs to another. 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.SEOPress
Measured on 10.2: +24.5 ms front-end, +1 queries, 0 JSON-LD types, 1 custom tables
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.
Rank Math
Measured on 1.0.278: +36.1 ms front-end, +16 queries, 6 JSON-LD types, 6 custom tables
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.Yoast SEO
Measured on 28.4: +39 ms front-end, +3 queries, 12 JSON-LD types, 6 custom tables
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.All in One SEO
Measured on 5.0.1.1: +53.5 ms front-end, +22 queries, 8 JSON-LD types, 9 custom tables
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
| Measured | Slim SEO 4.10.1 | The SEO Framework 5.1.4 | Hydrogen SEO 0.0.18 | SEOPress 10.2 | Rank Math 1.0.278 | Yoast SEO 28.4 | All 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 default | Yes | Yes | Yes | Yes | Yes | No | Yes |
| JSON-LD types printed | 10 | 9 | 10 | 0 | 6 | 12 | 8 |
| Open Graph / X tags | 11 / 2 | 10 / 5 | 10 / 5 | 10 / 6 | 11 / 8 | 10 / 5 | 6 / 3 |
| Sitemap URLs listed | 73 | 51 | 72 | 58 | 59 | 75 | 73 |
| Sitemap image entries | 40 | 0 | 40 | 40 | 0 | 40 | 0 |
lastmod coverage | 50 / 73 | 51 / 51 | 72 / 72 | 50 / 58 | 59 / 59 | 74 / 75 | 73 / 73 |
| Custom database tables | 0 | 0 | 1 (2 with the 404 Monitor on) | 1 | 6 | 6 | 9 |
| 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 size | 1.4 MB | 2.9 MB | 4.6 MB | 11.7 MB | 15.1 MB | 21 MB | 24.4 MB |
| Block editor assets | 14 files, 187.7 KB | 25 files, 77.6 KB | 2 files, 700.4 KB | 17 files, 217 KB | 24 files, 1,792 KB | 48 files, 4,160 KB | 130 files, 3,543 KB |
| After deactivation | Releases everything | Releases everything (exact baseline) | +0.2 KB left autoloading | No reduction at all | +11.0 KB still autoloading | +2.6 KB left autoloading, 6 tables remain | No 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. Each column heading names the version that was measured. Bold marks the better number in each row. Full method: how we tested.
Hydrogen SEO's figures were measured on 0.0.18 and have not been re-run on later versions. The custom tables row is the exception: it is counted from the 0.0.31 source. A default install has one table, for the internal link counter. Switching on the 404 Monitor, which is off by default, creates a second for its log. Deleting the plugin removes both.
Features: free, paid or not offered
| Feature | Slim SEO 4.11.5 | The SEO Framework 5.2.1 | Hydrogen SEO 0.0.31 | SEOPress 10.4 | Rank Math 1.0.282 | Yoast SEO 28.8 | All in One SEO 5.0.5 |
|---|---|---|---|---|---|---|---|
| Search engine verification codes | — | Free | Free | Free | Free | Free | Free |
| IndexNow instant indexing | — | — | Free | Free | Free | Paid | Paid |
| Redirect manager | Free | — | Free | Paid | Free | Paid | Paid |
| 404 monitor | Free | No | Free | Paid | Free | — | Paid |
| SEO column on the Posts screen | Free | Free | Free | Free | Free | Free | Free |
| SEO fields in Quick Edit | Free | Free | Free | Free | Paid | — | — |
| Attachment page redirects | Free | — | Free | Free | Free | Free | Free |
| Author and date archive controls | — | Free | Free | Free | Free | Free | Free |
| RSS feed text | — | — | Free | — | Free | Free | Free |
| max-snippet and preview controls | — | Free | Free | — | Free | — | Free |
| Primary category | Free | Free | Free | Free | Free | Free | Paid |
| Internal link counts on the Posts screen | — | — | Free | Free | Free | Free | — |
| Automatic image alt attributes | Free | — | Free | Free | Free | — | Paid |
| Table of contents block | — | — | Free | — | Free | Paid | Free |
| HTML sitemap | — | — | Free | Free | Free | — | Free |
| Pillar or cornerstone content flag | — | — | Free | — | Free | Free | Paid |
| Crawl cleanup switches | — | — | Free | Free | — | Free | — |
| Video sitemap | — | — | Free | Paid | Paid | Paid | Paid |
| Google News sitemap | Free | — | Free | Paid | Paid | Paid | Paid |
| llms.txt | — | — | Free | Paid | Free | Free | Free |
This table is not benchmark data. It is based on each plugin's WordPress.org listing, the code of its free version there, and its official documentation and pricing pages, checked on 12 November 2026, for the version in each column heading. Free means the feature is in the plugin's own free version. Paid means it needs that plugin's paid version or a paid add-on. No means the plugin's listing says it does not offer it. A dash means we could not confirm it either way; it does not mean the feature is missing. A row says a feature exists, not how complete it is. Plugins change, so check the plugin's own site before relying on a cell. If a cell is wrong, tell us and we will correct it.
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.