AltPost – Free AI Alt Text, No API Keys
AltPost is a free AI alt text generator for WordPress that writes clear image descriptions and SEO-ready alt text for your media library. There is no API key to create and no OpenAI account to manage — AltPost Managed handles the AI for you. Just install, register your email for the free tier, and run.
Built by A63 Digital, a working WordPress agency in Dublin, Ireland.
Included in this free plugin
- Vision-based alt text — the AI actually sees and describes your images
- Batch runner with Start / Pause / Stop controls
- Inline editable results table with debounced autosave
- Rollback to previous alt text with one click
- Filename-as-alt detection (treats
IMG_1234.jpgas missing) - Compatibility with major page builders (Gutenberg, Elementor, Beaver Builder, Divi, WPBakery, Bricks, Oxygen)
- Cache plugin support (WP Rocket, W3 Total Cache, LiteSpeed Cache, and others)
Use AltPost as an alt text checker: it scans your media library for images with missing alt text or filename-based placeholders such as IMG_1234.jpg, then lets you generate proper descriptions for those images in bulk.
Meaningful alt text is required under WCAG 2.1 and the European Accessibility Act (in force since June 2025). AltPost helps WordPress sites meet those accessibility requirements by generating accurate, human-readable alt text at scale.
Free tier (service credits)
Start with 10 AI-generated images per month — register your email during setup (no credit card required). Credits are enforced by the AltPost Managed API (api.a63.ai), not by locking PHP features inside this plugin.
AltPost Pro (separate plugin — not in this zip)
Advanced features (context-aware SEO alt text, background processing, Image Manager, Broken Image Scanner, title & description generation, higher monthly limits) ship in a separate AltPost Pro plugin from a63.ai/altpost. This WordPress.org build does not include those modules and does not gate them behind a license key.
External services
This plugin connects to AltPost Managed at https://api.a63.ai.
When you generate alt text, the plugin sends a request to https://api.a63.ai/api/altpost/v1/vision. Each request includes:
- the public URL of the image being described
- the requested quality tier, language, and maximum length
- your site URL and the plugin version (sent as request headers)
The service calls an AI vision provider on your behalf, tracks your monthly credit usage, and returns the generated text plus your remaining credits. Images are not retained after processing.
Free-tier users also submit a registration request to https://api.a63.ai/api/altpost/v1/register-free during setup. This sends your email address, site URL, plugin version, and optional marketing consent preference (opt-in only — not required to use the free tier).
- Terms of Service: https://a63.ai/terms-of-service/
- Privacy Policy: https://a63.ai/privacy-policy/