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NEF to ICO Converter

Convert NEF to ICO online for free. Fast, secure, and high-quality conversion with no sign-up or software required.

Free to useNo file stored beyond 1 hourEncrypted over TLS 1.2/1.3No watermarks

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How it works

Three steps to your converted file

Everything happens in your browser tab - upload, pick a format, download. The heavy lifting runs on our servers.

01

Upload your file

Drag and drop, click to browse, or paste a URL. Batches take up to 20 files at once - 230+ input formats across video, audio, image, document, and archive types.

02

Choose an output format

Pick from over a hundred output formats. Filter by category or search by name - every option is open to everyone, no account needed.

03

Convert & download

Hit Convert and grab your download link moments later. Originals are erased when the job completes; results are cleared within about an hour.

What is an NEF file?

The Nikon Electronic Format (NEF) is a proprietary raw image container exclusively used by Nikon digital cameras, structured around the TIFF (Tagged Image File Format) specification. It stores raw 12-bit or 14-bit data captured by the image sensor without in-camera processing, alongside extensive metadata including EXIF data, Picture Control settings, and lens identification. The format supports both lossless and lossy compression variations and encapsulates a full-resolution JPEG preview within the file structure for quick referencing.

How to open an NEF file

Microsoft Windows (with the Microsoft Camera Codec Pack) and macOS Preview offer native support for viewing NEF files. For professional editing and raw conversion, Nikon provides the proprietary NX Studio software. Third-party industry-standard applications such as Adobe Photoshop, Corel AfterShot Pro, and the open-source editor GIMP (utilizing Darktable or RawTherapee as a backend) allow for manipulation of the raw sensor data.

NEF Technical Info

Full Name
Nikon Electronic Format
Developed By
Nikon Corporation
Initial Release
1999
MIME Type
image/x-nikon-nef

What is an ICO file?

The ICO format is an image container specifically designed for Microsoft Windows to store icons for executable files, folders, and applications. Introduced with Windows 1.0, it can encapsulate multiple raster images of varying dimensions and color depths (specifically BMP or PNG frames) within a single file to support dynamic scaling across different display resolutions. The structure comprises an ICONDIR header referencing one or more ICONDIRENTRY directory entries, allowing the operating system to select the appropriate 16x16, 32x32, or 48x48 pixel resource based on the current UI scaling settings.

How to open an ICO file

ICO files are natively supported by the Microsoft Windows operating system, which automatically renders them in the File Explorer and taskbar. On macOS, Apple Preview handles the format natively. For editing or detailed inspection of the contained bitmap layers, raster graphics editors such as GIMP, Adobe Photoshop (via plugin), or Paint.NET are required. Web browsers also natively render ICO files when they are designated as favicons.

ICO Technical Info

Full Name
Microsoft Icon File
Developed By
Microsoft
Initial Release
1985
MIME Type
image/vnd.microsoft.icon

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Why RunConvert

The fastest way to convert any file

Purpose-built for speed, privacy, and breadth of format support.

Convert NEF to ICO in seconds

Every NEF to ICO conversion runs on our servers, so your device stays fast and the output quality stays intact.

Fast, cloud-powered

No queue, no waiting. Files are processed on high-performance servers and returned in seconds, even for large files.

Secure & private

Encrypted in transit and never shared with anyone. Uploads are erased the moment your job completes, and results shortly after.

Free - no account needed

Convert without creating an account - no credit card, no trial clock. Sign in only if you want history and higher daily limits.

Developer API

Convert NEF to ICO via API

Automate NEF to ICO conversions in three steps: create a job, upload your file, then poll for the result.

# 1. Create job
curl -X POST https://api.runconvert.com/v3/jobs \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "tag": "nef-to-ico",
    "tasks": {
      "upload-file": {
        "operation": "import/upload"
      },
      "convert": {
        "operation": "convert",
        "input": "upload-file",
        "output_format": "ico"
      },
      "export-result": {
        "operation": "export/url",
        "input": "convert"
      }
    }
  }'

# 2. Upload your file (use upload_url from the response)
curl -X PUT "$UPLOAD_URL" --upload-file input.nef

# 3. Poll for result
curl https://api.runconvert.com/v3/jobs/$JOB_ID?include=tasks \
  -H "Authorization: Bearer YOUR_API_KEY"

Replace YOUR_API_KEY with your RunConvert API key. Get your free API key at runconvert.com/api.