# img-src.io

> img-src.io is an image CDN service that lets developers upload images once and serve them globally with real-time transformations via URL parameters. It supports automatic format conversion (WebP, AVIF, JXL, JPEG, PNG), resizing, cropping, and quality optimization — all at the edge with 200+ Cloudflare locations worldwide.

> For complete documentation in a single file, see: https://img-src.io/llms-full.txt

## What img-src.io Does

img-src.io is a developer-focused image hosting and CDN platform. You upload an image through the dashboard or REST API, and receive a permanent CDN URL. You can then transform that image on-the-fly by appending URL parameters — no build step, no image pipeline, no configuration required.

**Core capabilities:**

- Upload images via web dashboard or REST API
- Automatic global CDN delivery via Cloudflare (200+ edge locations)
- Real-time image transformation through URL parameters
- Format conversion: WebP (25-34% smaller), AVIF (50%+ smaller), JXL (next-gen), JPEG, PNG
- Resize, crop, and quality adjustment at the edge
- Hash-based deduplication (no duplicate storage charges)
- Immutable cache headers for optimal browser caching
- Zero egress/bandwidth fees on all plans

## How Image URLs Work

Every uploaded image gets a CDN URL in this format:

```
https://img-src.io/i/{username}/{filename}
```

Transform images by adding URL parameters:

- `?w=800` — Resize width to 800px
- `?h=600` — Resize height to 600px
- `?w=800&h=600&fit=cover` — Resize and crop to exact dimensions
- `?q=85` — Set quality to 85%
- Change the file extension to convert format: `photo.webp`, `photo.avif`, `photo.jxl`, `photo.jpg`

Example: `https://img-src.io/i/john/photo.webp?w=800&q=85` serves a WebP image resized to 800px width at 85% quality.

**Fit modes:** `cover` (crop to fill), `contain` (fit within), `fill` (stretch), `scale-down` (only shrink)

## Pricing

**Free plan ($0/month):**

- 100 image uploads per month
- 10 GB storage
- 1,000 transformations per month
- 1,000 API requests per month
- 100 API requests per minute rate limit
- Unlimited CDN requests (serving)
- No bandwidth fees
- Supports JPEG, PNG, WebP, GIF, HEIC/HEIF, SVG, BMP, TIFF, AVIF, and more

**Pro plan ($5/month):**

- Everything in Free, plus:
- Unlimited image uploads per month
- 50 GB storage
- 10,000 transformations per month
- 10,000 API requests per month
- 500 API requests per minute rate limit
- Access Links for private/signed image URLs
- Image presets (e.g., `?p:thumbnail`, `?p:hero`)

**Resource Pack ($10/pack, Pro users only):**

- +10 GB storage, +10,000 API requests, +10,000 transformations

## REST API

The API uses Bearer token authentication. Create API keys in the dashboard under Settings.

**Base URL:** `https://img-src.io/api/v1`

**Key endpoints:**

- `POST /images` — Upload an image (multipart/form-data, max 5MB)
- `GET /images` — List your images
- `GET /images/search` — Search images by filename
- `GET /images/:id` — Get image metadata
- `DELETE /images/:id` — Delete an image
- `POST /images/:id/signed-url` — Create a signed/temporary URL (Pro)
- `GET /usage` — Get current usage statistics
- `GET /settings` — Get account settings
- `POST /settings/api-keys` — Create a new API key
- `GET /settings/presets` — List image presets (Pro)
- `POST /settings/presets` — Create an image preset (Pro)

**Rate limits:** Free: 100 req/min, Pro: 500 req/min. Rate limit headers: `X-RateLimit-Limit`, `X-RateLimit-Remaining`, `X-RateLimit-Reset`.

## Supported Image Formats

**Input (upload):** JPEG, PNG, WebP, GIF, BMP, TIFF, ICO, SVG, HEIC/HEIF, AVIF, JXL, TGA, PNM, QOI, HDR, EXR

**Output (serve):** WebP (default), AVIF (max 8 megapixels), JXL, JPEG, PNG

**AVIF limitation:** Maximum 8 megapixels (~3500x2300px), maximum 4000px on any dimension.

## Architecture

img-src.io runs entirely on Cloudflare's edge infrastructure:

- **Frontend:** React 19 on Cloudflare Pages
- **Backend API:** TypeScript on Cloudflare Workers (Hono framework)
- **CDN:** Cloudflare Workers + optional Rust container for native codec support
- **Storage:** Cloudflare R2 (objects), KV (cache), D1 (metadata)
- **Auth:** Clerk (JWT/JWKS)

## FAQ

**What counts as a transformation?**
A transformation is any request that modifies the image — resize, format conversion, or quality adjustment. Cached responses from the CDN do not count toward your transformation limit.

**What happens when I reach my limit?**
On the Free plan, uploads and transformations are blocked until the next billing cycle. On the Pro plan, you can purchase Resource Packs to extend your quota instantly.

**Can I downgrade from Pro to Free?**
Yes. Cancel anytime. Your images remain accessible, but you'll be limited to Free plan quotas after the billing period ends.

**Is there a bandwidth limit?**
No. Cloudflare R2 has zero egress fees, so img-src.io offers unlimited bandwidth on all plans at no extra cost.

**What is an Access Link?**
Access Links are signed, time-limited URLs for private images. They are available on the Pro plan and allow you to share images that expire after a set duration.

**What are image presets?**
Presets are saved transformation configurations (e.g., `p:thumbnail` = `w=200&h=200&fit=cover`). Define them once in the dashboard, then use `?p:name` in any image URL. Pro plan only.

## Links

- [Homepage](https://img-src.io)
- [Pricing](https://img-src.io/pricing)
- [Documentation](https://docs.img-src.io)
- [About](https://img-src.io/about)
- [API Reference](https://docs.img-src.io)
- [Terms of Service](https://img-src.io/terms-of-service)
- [Privacy Policy](https://img-src.io/privacy-policy)