Free Content Moderation API: The Best Options, and When Free Isn't Enough
You can moderate content for free, and for a lot of apps that is the right start. Here are the genuinely free content moderation APIs in 2026, what each covers, and the point where you outgrow them.
Key takeaways
- • Best free for text: OpenAI Moderation (text + images) and Google Perspective (toxicity).
- • Free for images: ModerateContent, and Clarifai's free community tier.
- • The catch: free means fixed categories, no custom policy, and often no PII, spam, or data residency.
- • When you outgrow it: a paid API like Paxmod, with a 14-day free trial and plans from $29/month.
The free options
| API | Covers | Good for |
|---|---|---|
| OpenAI Moderation | Text + images, fixed harm categories | The best free baseline overall |
| Google Perspective | Text toxicity attributes | Scoring comment toxicity |
| ModerateContent | Image ratings | Simple image screening |
| Clarifai (free tier) | Image/video models, limited volume | Prototyping visual moderation |
| Paxmod (14-day free trial) | Text + images, 13 categories, custom policy | Outgrowing the free options, plans from $29/month |
Free tiers and limits change; confirm current terms on each provider's site.
When free stops being enough
Free APIs are great until your policy stops matching theirs. You typically outgrow the free options when you need:
- A custom policy the fixed categories can't express (for example "allow mild swearing, block slurs and off-platform lures").
- PII or spam detection, which the free toxicity-focused options do not cover.
- Evasion resistance for leetspeak and unicode look-alikes.
- Data residency (EU/UK) for GDPR, or configurable thresholds.
At that point you do not have to jump to an expensive enterprise suite. Paxmod has a 14-day free trial, then plans from $29/month with 50,000 messages included, adding custom plain-English policies, PII detection, image moderation, and EU/UK data residency on one API. See the full pricing comparison.
Frequently Asked Questions
What is the best free content moderation API?
For text, OpenAI's free omni-moderation endpoint is the best overall; Perspective is free for toxicity; ModerateContent and Clarifai's free tier cover images.
Are free moderation APIs good enough for production?
If your needs match their fixed categories, yes. You outgrow free when you need custom policies, PII/spam, evasion resistance, or data residency.
Does Paxmod have a free tier?
No. Paxmod has a 14-day free trial (10,000 messages, all features) and a free, no-signup playground, then plans from $29/month, with custom policies and image moderation the free-only options lack.
Outgrown free? Try Paxmod for 14 days
Paxmod has a 14-day free trial (10,000 messages, all features), then plans from $29/month with 50,000 messages included and custom policies built in.