Compare
Convert.FAST API vs OpenAI Codex
OpenAI Codex offers code generation, not bulk format conversion
Convert.FAST APIConvert everything. Maintain nothing.
OpenAI CodexOpenAI's coding agent for the terminal, IDE and cloudWhich to pick
Pick Convert.FAST API if you want…
- 200+ format file conversion API
- The lower starting price: $9/month against $20/month
- Integrations with cURL, PowerShell or CLI wrappers (on Convert.FAST API's list, not OpenAI Codex's)
Pick OpenAI Codex if you want…
- Multi-agent coding workflows
- AI code completion
- Integrations with ChatGPT account or Plugins (on OpenAI Codex's list, not Convert.FAST API's)
Side by side
- What it is
- Convert.FAST API:Convert.FAST API is a REST API that converts files between 200+ formats with a single HTTP request.
- OpenAI Codex:OpenAI Codex is an AI coding agent that assists across terminal, IDE, and cloud for planning, building, refactoring, reviewing, and releasing code.
- Best for
- Convert.FAST API:200+ format file conversion API
- OpenAI Codex:Multi-agent coding workflows
- Who it’s for
- Convert.FAST API:Developers building server-side integrations or AI agents that need automated file conversion.
- OpenAI Codex:Developers and engineering teams needing AI-assisted coding and code review.
- Pricing
- Convert.FAST API:Freemium
- OpenAI Codex:Freemium
- Plans
- Convert.FAST API:Free $0 · Pro (monthly) $12/month per month · Pro (annual) $9/month per month · Pay-as-you-go From $5
- OpenAI Codex:Plus $20 per month · Pro $100 per month · Business $20 per user / month
- Works with
- Convert.FAST API:cURL, PowerShell, CLI wrappers
- OpenAI Codex:ChatGPT account, Plugins
Convert.FAST API features
- Wide format support. Convert between images, RAW photos, documents, audio, video, archives, fonts and ebooks.
- Async submit-poll-download flow. Three-step process (POST /convert, GET job status, GET download) for reliable conversions.
- CLI wrappers. Shell scripts (convert.fast.sh / .ps1) handle the full flow in one command.
- Webhook notifications. HMAC-signed callbacks alert when jobs complete, avoiding polling.
- AI-agent friendly docs. Auto-generated OpenAPI docs, SKILL.md and convenience scripts for LLM agents.
- High limits. Up to 1 GB per file, 6 parallel jobs (Pro) and 18 queued jobs per account.
OpenAI Codex features
- Parallel agent execution. Runs multiple coding agents simultaneously, using tools to verify work until requirements are met.
- Reusable cloud environments. Keeps tasks running in the cloud with per-repo environments that persist across devices.
- Automated PR reviews. Scans pull requests, surfaces findings, and answers questions to accelerate code review.
- Plugin ecosystem. Connects to external tools and adds specialized capabilities via plugins.
- Cross-platform access. Available in ChatGPT, IDE extensions, CLI, and web, all linked to a single account.
- Secure shared workspaces. Business plan offers admin controls and shared repositories for team collaboration.
Convert.FAST API vs OpenAI Codex FAQ
Is Convert.FAST API or OpenAI Codex free?+
Convert.FAST API has a free plan; paid plans start at $9/month (Pro (annual)). OpenAI Codex has a free plan; paid plans start at $20/month (Plus).
Which is cheaper, Convert.FAST API or OpenAI Codex?+
Convert.FAST API is cheaper to start with: Convert.FAST API's Pro (annual) plan ($9/month) against OpenAI Codex's Plus plan ($20/month).
Do Convert.FAST API and OpenAI Codex integrate with the same tools?+
Their integration lists don't overlap: Convert.FAST API lists cURL, PowerShell and CLI wrappers; OpenAI Codex lists ChatGPT account and Plugins.
On DevHunt
Based on each tool's website and DevHunt data. Details may change; check the official sites.