All in One SEO vs Slim SEO: guided setup against no setup at all
Slim SEO is the better choice unless you specifically want a guided, feature-rich admin. It added +10.0 ms and 2 queries per request against All in One SEO's +53.5 ms and 22, and it printed more schema and a sitemap with images. All in One SEO offers what Slim SEO deliberately leaves out: screens, settings and hand-holding.
Figures are from our seven-plugin benchmark, free versions at defaults on one WordPress 7.1 install. We build Hydrogen SEO, which is not in this pair.
The numbers
| Measured | All in One SEO 5.0.1.1 | Slim SEO 4.10.1 |
|---|---|---|
| Front-end PHP time added | +53.5 ms | +10 ms |
| Peak memory added | +14.5 MB | +2 MB |
| Database queries added | +22 | +2 |
| Hooks registered | +100 | +51 |
<head> bytes added | +6,668 | +1,649 |
| Meta description by default | Yes | Yes |
| JSON-LD types printed | 8 | 10 |
| Open Graph / X tags | 6 / 3 | 11 / 2 |
| Sitemap URLs listed | 73 | 73 |
| Sitemap image entries | 0 | 40 |
lastmod coverage | 73 / 73 | 50 / 73 |
| Custom database tables | 9 | 0 |
| Autoloaded options added | +14.6 KB | -0.2 KB |
| Plugin package size | 24.4 MB | 1.4 MB |
| Block editor assets | 130 files, 3,543 KB | 14 files, 187.7 KB |
| After deactivation | No reduction: 14.5 KB still autoloading | Releases everything |
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.
What the numbers mean
These two have opposite ideas of what an SEO plugin should be. All in One SEO shows you everything: a 511 KB dashboard, the heaviest admin page we measured, and 130 files (3,543 KB) in the block editor. Slim SEO shows you almost nothing: it added no admin menu items at all and loaded 187.7 KB into the editor.
The server costs follow the same line. All in One SEO used +14.5 MB of memory against Slim SEO's +2.0 MB, grew <head> by 6,668 bytes against 1,649 (the largest and smallest in the field), and ships 24.4 MB against 1.4 MB (also the largest and smallest). It creates nine custom tables; Slim SEO creates none. Its autoloaded options grew by 14.6 KB, while Slim SEO's came out fractionally below baseline. On deactivation Slim SEO released everything and All in One SEO released nothing.
Output mostly favors Slim SEO. It printed 10 JSON-LD types in 3,828 bytes against All in One SEO's 8 in 4,544. Its sitemap listed 73 URLs with all 40 featured images; All in One SEO's free sitemap listed 73 URLs with none. Slim SEO printed 11 Open Graph tags against 6. All in One SEO wins two rows: it printed 3 X tags against Slim SEO's 2, and it stamped lastmod on all 73 sitemap URLs, where Slim SEO left 23 unstamped. Both generate meta descriptions.
So the trade is not output for cost; Slim SEO gives you comparable or better output for a fraction of the cost. The trade is control and guidance. If you or your client want to see settings, follow a setup wizard and manage features from screens, All in One SEO provides that and Slim SEO does not.
Choose All in One SEO if
- You want a guided setup and a full settings interface.
- You want
lastmodon every sitemap URL. - You want many features and add-ons in one product family.
- You are handing the site to someone who expects visible SEO screens.
Choose Slim SEO if
- You want the smallest footprint: 1.4 MB package, +1,649 head bytes, no tables.
- You want more schema and featured images in the sitemap at defaults.
- You want nothing left behind after deactivation.
- You want a plugin you install and then never think about.
Switching between them
Slim SEO includes a migration tool that can import from All in One SEO, and All in One SEO has importers for several major plugins; check each plugin's documentation for current sources. All in One SEO keeps per-post data in its own tables, so migrate before you uninstall it. Slim SEO has few settings to map, so focus your checks on per-post titles, descriptions and redirects. Hydrogen SEO imports from both; see switch from another SEO plugin.
Common questions
Is Slim SEO lighter than All in One SEO?
Much lighter in our benchmark: +10.0 ms and 2 queries against +53.5 ms and 22, with a 1.4 MB package against 24.4 MB and no tables against nine.
Does Slim SEO have a settings dashboard?
Very little. It added no admin menu items in our test and works from defaults. All in One SEO has a full dashboard, which measured 511 KB.
Which prints more schema?
Slim SEO: 10 JSON-LD types in 3,828 bytes against All in One SEO's 8 in 4,544 bytes.