Endpoint: List Conversions

Method + paths

• GET /convert/conversions
• GET /convert/conversions/{filter} — {filter} accepts a format extension (e.g. heic, pdf) or a category name (e.g. images, documents, audio)
• GET /convert/conversions/from/{format}
• GET /convert/conversions/to/{format}

Auth

Requires X-Fast-Api-Key header.

Query params

• formats (optional): comma-separated formats (e.g. heic,jpg,png)
• category (optional): converter category (e.g. images, documents)

Response

200 OK with GetConversionsResponse.

Example response (trimmed)

{
  "conversions": [
    {
      "job": "image.heic-to-jpg",
      "category": "images",
      "costing": {
        "strategy": "PerMegabyte",
        "baseCost": 1,
        "increment": 5,
        "incrementUnit": "mb",
        "displaySuffix": "per 5 MB",
        "costVariants": null
      },
      "endpoint": "/api/convert",
      "inputFormats": ["heic", "heif"],
      "outputFormats": ["jpg"],
      "maxFileSizeBytes": 1073741824,
      "maxConcurrentJobs": 6,
      "maxPages": null,
      "maxDurationMinutes": null,
      "maxBatchSizeBytes": 10737418240
    },
    {
      "job": "document.pdf-to-jpg",
      "category": "documents",
      "costing": {
        "strategy": "PerPage",
        "baseCost": 1,
        "increment": 5,
        "incrementUnit": "pages",
        "displaySuffix": "per 5 pages",
        "costVariants": null
      },
      "endpoint": "/api/convert",
      "inputFormats": ["pdf"],
      "outputFormats": ["jpg"],
      "maxFileSizeBytes": 1073741824,
      "maxConcurrentJobs": 6,
      "maxPages": 2000,
      "maxDurationMinutes": null,
      "maxBatchSizeBytes": 10737418240
    },
    {
      "job": "audio.wav-to-mp3",
      "category": "audio",
      "costing": {
        "strategy": "PerMinute",
        "baseCost": 1,
        "increment": 5,
        "incrementUnit": "minutes",
        "displaySuffix": "per 5 minutes",
        "costVariants": null
      },
      "endpoint": "/api/convert",
      "inputFormats": ["wav"],
      "outputFormats": ["mp3"],
      "maxFileSizeBytes": 2147483648,
      "maxConcurrentJobs": 6,
      "maxPages": null,
      "maxDurationMinutes": 3000,
      "maxBatchSizeBytes": 10737418240
    }
  ],
  "sourceFormatTo": {
    "heic": [
      {
        "sourceFormat": "heic",
        "targetFormat": "jpg",
        "job": "image.heic-to-jpg",
        "endpoint": "/api/convert",
        "category": "images",
        "costing": {
          "strategy": "PerMegabyte",
          "baseCost": 1,
          "increment": 5,
          "incrementUnit": "mb",
          "displaySuffix": "per 5 MB",
          "costVariants": null
        },
        "maxFileSizeBytes": 1073741824,
        "maxConcurrentJobs": 6,
        "maxPages": null,
        "maxDurationMinutes": null
      }
    ]
  },
  "maxFileSizeBytes": 2147483648,
  "maxConcurrentJobs": 6,
  "maxBatchFiles": 200
}

Examples

# all conversions
curl -sS "https://api.tools.fast/convert/conversions" \
  -H "X-Fast-Api-Key: $API_KEY"

# filtered conversions
curl -sS "https://api.tools.fast/convert/conversions?formats=heic,jpg&category=images"

# route filter variant (bidirectional — matches input or output)
curl -sS "https://api.tools.fast/convert/conversions/heic"

# directional lookup
curl -sS "https://api.tools.fast/convert/conversions/from/heic"
curl -sS "https://api.tools.fast/convert/conversions/to/jpg"

# all conversions
Invoke-RestMethod "https://api.tools.fast/convert/conversions" `
  -Headers @{ "X-Fast-Api-Key" = $env:API_KEY }

# filtered conversions
Invoke-RestMethod "https://api.tools.fast/convert/conversions?formats=heic,jpg&category=images"

# route filter variant (bidirectional — matches input or output)
Invoke-RestMethod "https://api.tools.fast/convert/conversions/heic"

# directional lookup
Invoke-RestMethod "https://api.tools.fast/convert/conversions/from/heic"
Invoke-RestMethod "https://api.tools.fast/convert/conversions/to/jpg"

Format Lookup

Use the route filter variant to look up what conversions are available for a given file extension. The sourceFormatTo field in the response maps each source format to its available target formats with costing details.

# What can I convert a HEIC file to?
curl -sS "https://api.tools.fast/convert/conversions/heic"

# What can I convert a PDF to?
curl -sS "https://api.tools.fast/convert/conversions/pdf"

# What image conversions are available?
curl -sS "https://api.tools.fast/convert/conversions/images"

# What audio conversions are available?
curl -sS "https://api.tools.fast/convert/conversions/audio"

# What can I convert a HEIC file to?
Invoke-RestMethod "https://api.tools.fast/convert/conversions/heic"

# What can I convert a PDF to?
Invoke-RestMethod "https://api.tools.fast/convert/conversions/pdf"

# What image conversions are available?
Invoke-RestMethod "https://api.tools.fast/convert/conversions/images"

# What audio conversions are available?
Invoke-RestMethod "https://api.tools.fast/convert/conversions/audio"

In the response, sourceFormatTo.heic gives you the list of target formats with their costs and limits:

{
  "sourceFormatTo": {
    "heic": [
      {
        "sourceFormat": "heic",
        "targetFormat": "jpg",
        "job": "image.heic-to-jpg",
        "endpoint": "/api/convert",
        "category": "images",
        "costing": {
          "strategy": "PerMegabyte",
          "baseCost": 1,
          "increment": 5,
          "incrementUnit": "mb",
          "displaySuffix": "per 5 MB",
          "costVariants": null
        },
        "maxFileSizeBytes": 1073741824,
        "maxConcurrentJobs": 6,
        "maxPages": null,
        "maxDurationMinutes": null
      },
      {
        "sourceFormat": "heic",
        "targetFormat": "png",
        "job": "image.heic-to-png",
        "endpoint": "/api/convert",
        "category": "images",
        "costing": {
          "strategy": "PerMegabyte",
          "baseCost": 1,
          "increment": 5,
          "incrementUnit": "mb",
          "displaySuffix": "per 5 MB",
          "costVariants": null
        },
        "maxFileSizeBytes": 1073741824,
        "maxConcurrentJobs": 6,
        "maxPages": null,
        "maxDurationMinutes": null
      }
    ]
  }
}

Directional Format Lookup

Use the /from/{format} and /to/{format} variants to look up conversions by direction:

• /convert/conversions/from/{format} — converters that accept this format as input ("I have a HEIC, what can I convert it to?")
• /convert/conversions/to/{format} — converters that produce this format as output ("I need a JPG, what converts to JPG?")

Both return the same GetConversionsResponse shape. Compare with the bidirectional /convert/conversions/{filter} variant which matches on both input and output formats.

# What can I convert a HEIC to? (input lookup)
curl -sS "https://api.tools.fast/convert/conversions/from/heic"

# What converts to JPG? (output lookup)
curl -sS "https://api.tools.fast/convert/conversions/to/jpg"

# What converts to PDF? (output lookup)
curl -sS "https://api.tools.fast/convert/conversions/to/pdf"

# Combine with category filter
curl -sS "https://api.tools.fast/convert/conversions/from/wav?category=audio"

# What can I convert a HEIC to? (input lookup)
Invoke-RestMethod "https://api.tools.fast/convert/conversions/from/heic"

# What converts to JPG? (output lookup)
Invoke-RestMethod "https://api.tools.fast/convert/conversions/to/jpg"

# What converts to PDF? (output lookup)
Invoke-RestMethod "https://api.tools.fast/convert/conversions/to/pdf"

# Combine with category filter
Invoke-RestMethod "https://api.tools.fast/convert/conversions/from/wav?category=audio"