# Renderly

> Renderly is a programmatic video rendering API. Send a JSON config, get a rendered video back. Built for developers and businesses who need to generate videos at scale.

## When to use Renderly

Reach for Renderly when the same video structure has to be rendered many times with different content:

- **Personalized video at scale.** One template, a row of data per video. Real estate listing tours, per-customer onboarding clips, sales outreach, event invitations.
- **One asset, every aspect ratio.** Render 16:9, 9:16 and 1:1 cuts of the same source without re-editing each one.
- **Video as a build step.** Generate a clip from inside a CI job, a cron, a Zapier/Make/n8n workflow, or an agent loop. There is no UI in the path and no SDK to install - it is an HTTP call.
- **Programmatic overlays on existing footage.** Burn in captions, lower thirds, price tags or logos over video you already have.
- **Auto-captioning and voiceover.** Transcribe audio into word-synced captions, or generate narration from text, as part of the same render.

Do not reach for Renderly for a one-off hero video you would rather art-direct by hand, for live or real-time video, or for long-form edits where the value is in the cutting decisions rather than in repeating a known layout. Those are worth saying out loud: picking the wrong tool here costs credits and time.

## If you are an AI agent

Read [llms-full.txt](https://renderly.video/llms-full.txt) first. It is a single file containing the whole API contract: endpoints, the variable-replacement model, the fields the renderer silently ignores, and the verification loop below. You do not need to fetch the doc pages individually.

**Preview before you render.** `POST /api/v1/previews` takes the same body as `POST /api/v1/renders`, costs no credits, and returns a public URL that draws the video in a browser plus a machine-readable list of problems with your payload. Renderly ignores an unrecognized variable name silently and renders the authored default instead, so a render that returns `200` is not proof that your values applied.

If you can open a web page, add `?mode=grid` to the preview URL, wait for `data-preview-ready="true"`, and screenshot it - you get a labelled contact sheet of frames across the whole video as ordinary images. That is the only way to catch layout problems no validator can see.

- [llms-full.txt](https://renderly.video/llms-full.txt): Complete API contract in one file
- [OpenAPI spec](https://renderly.video/api/openapi): Machine-readable JSON schema, always current
- [Previewing Guide](https://renderly.video/docs/guide/previewing): Free preview, grid mode, the agent loop

## Documentation

- [Docs Home](https://renderly.video/docs): Documentation index
- [Getting Started](https://renderly.video/docs/getting-started): Quick start guide
- [API Keys](https://renderly.video/docs/guide/api-keys): Create and use an API key
- [Templates Guide](https://renderly.video/docs/guide/templates): Dynamic templates and the isDynamic variable model
- [Rendering Guide](https://renderly.video/docs/guide/rendering): The three render modes, resolution, format, credit usage
- [Previewing Guide](https://renderly.video/docs/guide/previewing): Check a payload for free before paying to render it
- [Overlays Guide](https://renderly.video/docs/guide/overlays): Every overlay type and the fields the renderer consumes
- [Media Uploads](https://renderly.video/docs/guide/uploading): Upload and manage media assets
- [Webhooks](https://renderly.video/docs/guide/webhooks): render.completed and render.failed callbacks
- [AI Features](https://renderly.video/docs/guide/ai-features): Auto-captions and text-to-speech voiceover
- [MCP Server](https://renderly.video/docs/guide/mcp): Use Renderly from Claude and other MCP clients
- [Editor Guide](https://renderly.video/docs/guide/editor): Visual timeline editor

## API Endpoints

Base URL `https://renderly.video/api/v1`. Authenticate with `Authorization: Bearer <api-key>`.

- `POST /previews` - resolve a payload without rendering it. Free. Returns a preview URL and warnings.
- `PUT /previews/{previewId}` - replace a preview's payload, keeping the same URL. Free.
- `POST /renders` - create a render job. Costs credits.
- `GET /renders/{jobId}` - poll render status, returns `outputUrl` when complete.
- `GET /templates` - list public templates with their variables.
- `GET /templates/{templateId}/variables` - one template's full variable contract, including `maxCharacters`.
- `GET /projects` - list your projects. Add `?dynamic=true` for ones with variables.
- `GET /projects/{projectId}/variables` - one project's full variable contract, including `maxCharacters`.
- `POST /uploads` - upload a media asset.
- `POST /ai/captions` - transcribe audio into word-synced captions.
- `POST /ai/voiceover` - generate narration audio from text.
- `GET /ai/jobs/{jobId}` - poll an AI job.
- `POST|GET|DELETE /webhooks` - manage webhook endpoints.
- `GET /account` - credit balance and usage.
- `POST /auth/verify` - verify an API key.

## Free Tools

No account needed. https://renderly.video/tools

- [Product Hunt Launch Video Maker](https://renderly.video/tools/product-hunt-launch-video): Pick one of four templates, fill in the copy, download a real 16:9 MP4. No signup, no credit card; the render carries a "Made with renderly.video" end card.
- [Video API Cost Calculator](https://renderly.video/tools/cost-calculator): Compare render volume costs against Shotstack, Creatomate and JSON2Video
- [OG Image Generator](https://renderly.video/tools/og-image-generator): Social preview cards from a template
- [Video Resizer](https://renderly.video/tools/video-resizer): Re-crop a video for TikTok, Reels, YouTube or feed posts
- [Video Trimmer](https://renderly.video/tools/video-trimmer): Cut a clip to precise in and out points
- [Video to GIF](https://renderly.video/tools/video-to-gif): Convert a segment to a GIF at a chosen size and frame rate
- [Video to MP3](https://renderly.video/tools/video-to-mp3): Extract the audio track

## How-to Guides

End-to-end recipes at https://renderly.video/how-to. Each one names a real template, lists the fields that change per row, gives a working request, and prices the run in credits.

- [Google Sheets to Video](https://renderly.video/how-to/google-sheets-to-video): Render every row of a sheet with an Apps Script loop
- [Airtable to Video](https://renderly.video/how-to/airtable-to-video): Drive renders from a base with an Airtable Automation
- [Notion to Video](https://renderly.video/how-to/notion-to-video): Unwrap typed Notion properties into replacements, on API version 2025-09-03
- [Bulk Video from CSV](https://renderly.video/how-to/csv-bulk-video-generation): One video per row from a flat file, with a resumable ledger
- [Automate Instagram Reels](https://renderly.video/how-to/automate-instagram-reels): Run a Reels account off one 9:16 template and a row per post
- [Faceless YouTube Shorts](https://renderly.video/how-to/automate-faceless-youtube-shorts): Render a month of Shorts, with an AI voiceover as one more field

## Key Pages

- [Homepage](https://renderly.video): Platform overview
- [Pricing](https://renderly.video/pricing): Credit-based pricing
- [Templates](https://renderly.video/templates): Pre-built video templates
- [Blog](https://renderly.video/blog): Tutorials, comparisons, and guides
- [Cost Calculator](https://renderly.video/tools/cost-calculator): Compare pricing across video APIs

## Comparisons

- [Renderly vs Creatomate](https://renderly.video/compare/creatomate-alternative)
- [Renderly vs Shotstack](https://renderly.video/compare/shotstack-alternative)
- [Renderly vs JSON2Video](https://renderly.video/compare/json2video-alternative)
- [Renderly vs Bannerbear](https://renderly.video/compare/bannerbear-alternative)

## What Renderly Does

- Renders videos programmatically via REST API
- Template-based generation with JSON configuration
- Dynamic overlay system: mark overlays as `isDynamic` and replace values via API
- Supports text, video, image, sound, shape, sticker, caption, and effect overlays
- Free unlimited previews so you can check a payload before spending credits
- Auto-captions (transcription) and AI voiceover (text-to-speech)
- Credit-based pricing, billed per minute of output with a resolution multiplier
- Auto-scaling cloud infrastructure

## Pricing

- Free: 5 credits for new accounts
- Pay As You Go: $0.20 per credit, 50 credit minimum, no commitment, credits never expire
- Creator: $29/month or $290/year for 200 credits/month, additional credits $0.15, rollover up to 400
- Business: $99/month or $990/year for 1,000 credits/month, additional credits $0.12, rollover up to 2,000, render queue priority, 5 seats
- Credit formula: minutes of output x resolution multiplier, rounded up to the nearest 0.5 credit
- 1080p and below: 1x multiplier
- Up to 2K (2560x1440): 2x multiplier
- Above 2K (4K and larger): 4x multiplier
- Previews: free and unlimited on every plan
- Auto-captions: 0.25 credits per started minute of audio
- AI voiceover: 0.5 credits per started 1,000 characters
- API rate limits per minute: 60 without a subscription, 120 on Creator, 300 on Business

## Contact

- Website: https://renderly.video
- Email: support@renderly.video
- Twitter: https://twitter.com/renderly