openapi: 3.0.3 info: title: RenderPix — HTML to Image API description: | Convert HTML to pixel-perfect PNG, JPEG, or WebP images via a pre-warmed Chromium pool. No cold starts. Bring your own HTML — no templates, no lock-in. ## Authentication All endpoints (except `/og` and `/demo/render`) require an API key. Pass it via the `X-API-Key` header or `?api_key` query parameter. ## Plans | Plan | Renders/month | Max Resolution | Scale | Full Page | Selector | |---------|--------------|----------------|-------|-----------|----------| | Free | 100 | 1280×720 | 1× | No | No | | Starter | 2,000 | 1920×1080 | 2× | No | No | | Pro | 10,000 | 3840×2160 | 3× | Yes | Yes | | Scale | 50,000 | 3840×2160 | 3× | Yes | Yes | version: "1.1.0" contact: email: hello@renderpix.dev url: https://renderpix.dev x-logo: url: https://renderpix.dev/logo-icon.png servers: - url: https://renderpix.dev description: Production security: - ApiKeyHeader: [] - ApiKeyQuery: [] tags: - name: Render description: HTML and URL to image rendering - name: Free Tools description: No auth required — rate limited paths: /v1/render: post: tags: [Render] summary: HTML to Image description: | POST raw HTML, get back a PNG, JPEG, or WebP image. Rendered with a real Chromium browser — full CSS, fonts, shadows, gradients. Supports template variables via `{{key}}` syntax when `vars` is provided. operationId: renderHtml requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/RenderRequest' examples: simple: summary: Simple OG image value: html: "

Hello RenderPix

" width: 1200 height: 630 format: png instagram_carousel: summary: Instagram carousel slide value: html: "

Slide 1

" width: 1080 height: 1350 format: jpeg quality: 90 template_vars: summary: Certificate with template variables value: html: "

Certificate for {{name}} — {{course}}

" width: 1200 height: 800 format: png vars: name: "Jane Doe" course: "Advanced Python" responses: '200': description: Image binary headers: X-Render-Time: description: Render duration in milliseconds schema: type: integer example: 234 X-Usage-Remaining: description: Remaining renders this billing period schema: type: integer example: 1843 X-Width: description: Output image width in pixels schema: type: integer X-Height: description: Output image height in pixels schema: type: integer content: image/png: schema: type: string format: binary image/jpeg: schema: type: string format: binary image/webp: schema: type: string format: binary '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '429': $ref: '#/components/responses/RateLimited' /v1/screenshot: get: tags: [Render] summary: URL to Image (Screenshot) description: | Capture a full-page or viewport screenshot of any public URL. Waits for network idle before capturing — JS-rendered pages work correctly. operationId: screenshotUrl parameters: - name: url in: query required: true description: Public URL to screenshot schema: type: string format: uri example: https://renderpix.dev - name: width in: query schema: type: integer default: 1280 minimum: 100 maximum: 3840 - name: height in: query schema: type: integer default: 720 minimum: 100 maximum: 2160 - name: format in: query schema: type: string enum: [png, jpeg, webp] default: png - name: quality in: query description: JPEG/WebP quality (1–100). Ignored for PNG. schema: type: integer minimum: 1 maximum: 100 default: 90 - name: scale in: query description: Device pixel ratio. Pro+ plan only above 1×. schema: type: number minimum: 0.5 maximum: 3 default: 1 - name: fullPage in: query description: Capture full scrollable page. Pro+ plan only. schema: type: boolean default: false - name: selector in: query description: CSS selector — capture only that element. Pro+ plan only. schema: type: string responses: '200': description: Image binary headers: X-Render-Time: schema: type: integer X-Usage-Remaining: schema: type: integer content: image/png: schema: type: string format: binary image/jpeg: schema: type: string format: binary image/webp: schema: type: string format: binary '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '429': $ref: '#/components/responses/RateLimited' /v1/batch: post: tags: [Render] summary: Batch HTML to Images description: | Render multiple HTML items in a single request. Returns a JSON array of results. Each item is rendered independently — failures are isolated per item. Starter plan: up to 10 items. Pro/Scale: up to 50 items. operationId: batchRender requestBody: required: true content: application/json: schema: type: object required: [items] properties: items: type: array minItems: 1 maxItems: 50 items: $ref: '#/components/schemas/RenderRequest' callback_url: type: string format: uri description: Optional webhook URL. If provided, returns 202 immediately and POSTs results when done. example: items: - html: "

" format: png - html: "

" format: jpeg responses: '200': description: Array of render results (synchronous) content: application/json: schema: type: object properties: results: type: array items: type: object properties: index: type: integer success: type: boolean image: type: string description: Base64-encoded image format: type: string duration_ms: type: integer error: type: string '202': description: Accepted — results will be POSTed to callback_url content: application/json: schema: type: object properties: job_id: type: string status: type: string example: queued '401': $ref: '#/components/responses/Unauthorized' '429': $ref: '#/components/responses/RateLimited' /og: get: tags: [Free Tools] summary: Free OG Image Generator (watermarked) description: | Generate Open Graph images without an API key. Output is watermarked with "Free tier · renderpix.dev". Watermark is removed for authenticated Starter+ users. Rate limited to 10 requests/minute per IP. operationId: generateOgImage parameters: - name: title in: query required: true schema: type: string example: My Awesome Blog Post - name: description in: query schema: type: string - name: width in: query schema: type: integer default: 1200 - name: height in: query schema: type: integer default: 630 responses: '200': description: Watermarked OG image (PNG) content: image/png: schema: type: string format: binary '429': $ref: '#/components/responses/RateLimited' /health: get: tags: [Free Tools] summary: Health Check operationId: healthCheck security: [] responses: '200': description: Service status content: application/json: schema: type: object properties: status: type: string example: ok uptime: type: number description: Uptime in seconds memory: type: number description: Memory usage in MB timestamp: type: string format: date-time components: securitySchemes: ApiKeyHeader: type: apiKey in: header name: X-API-Key description: Get your API key from https://renderpix.dev/dashboard.html ApiKeyQuery: type: apiKey in: query name: api_key description: Alternative to X-API-Key header schemas: RenderRequest: type: object required: [html] properties: html: type: string description: Raw HTML string to render. Max 50,000 characters. example: "

Hello World

" width: type: integer description: Viewport width in pixels default: 1280 minimum: 100 maximum: 3840 height: type: integer description: Viewport height in pixels default: 720 minimum: 100 maximum: 2160 format: type: string description: Output image format enum: [png, jpeg, webp] default: png quality: type: integer description: JPEG/WebP compression quality (1–100). Ignored for PNG. default: 90 minimum: 1 maximum: 100 scale: type: number description: Device pixel ratio (deviceScaleFactor). Values above 1× require Starter+ plan. default: 1 minimum: 0.5 maximum: 3 fullPage: type: boolean description: Capture the full scrollable page. Pro+ plan only. default: false selector: type: string description: CSS selector to capture only a specific element. Pro+ plan only. example: "#hero-section" waitUntil: type: string description: Playwright page load event to wait for before capturing. enum: [load, domcontentloaded, networkidle, commit] default: load vars: type: object description: Template variable substitutions. Keys replace {{key}} placeholders in HTML. additionalProperties: type: string example: name: "Jane Doe" course: "Advanced Python" date: "June 2026" Error: type: object properties: error: type: string message: type: string responses: BadRequest: description: Invalid request parameters content: application/json: schema: $ref: '#/components/schemas/Error' example: error: bad_request message: "html field is required" Unauthorized: description: Missing or invalid API key content: application/json: schema: $ref: '#/components/schemas/Error' example: error: unauthorized message: "Invalid or missing API key" RateLimited: description: Usage limit or rate limit exceeded content: application/json: schema: $ref: '#/components/schemas/Error' example: error: usage_limit_exceeded message: "Monthly render limit reached. Upgrade your plan at renderpix.dev"