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JPG Compressor

Compress JPEG images to reduce file size while preserving visual quality. Uses intelligent lossy compression to achieve significant size reductions.

Try JPG compression in the browser →

Compress.FAST uses this same API — what you see in the browser is what you get in code.

Quick reference

Job typeimage.jpg-compress
Categoryimages
EndpointPOST /compress/jpg
Input formats.jpg
Output formatsame as input
Costing1 credit per 5 MB
Max file size1 GB
Optionsresize

Example

cURL 
# 1) submit
JOB_ID=$(curl -sS -X POST "https://api.tools.fast/compress" \
  -H "X-Fast-Api-Key: $API_KEY" \
  -F "file=@photo.jpg" | jq -r '.id')

# 2) poll until complete
while true; do
  STATUS=$(curl -sS "https://api.tools.fast/compress/job/${JOB_ID}" \
    -H "X-Fast-Api-Key: $API_KEY" | jq -r '.status')
  [ "${STATUS}" = "Succeeded" ] && break
  [ "${STATUS}" = "Failed" ] || [ "${STATUS}" = "Canceled" ] && exit 1
  sleep 1
done

# 3) download
curl -sS "https://api.tools.fast/compress/job/${JOB_ID}/download" \
  -H "X-Fast-Api-Key: $API_KEY" \
  -o "photo-compressed.jpg"
C# 
using var http = new HttpClient();
http.DefaultRequestHeaders.Add("X-Fast-Api-Key", "fast_prod_your_key_here");

using var form = new MultipartFormDataContent();
form.Add(new ByteArrayContent(File.ReadAllBytes("photo.jpg")), "file", "photo.jpg");

var submit = await http.PostAsync("https://api.tools.fast/compress", form);
var job = await submit.Content.ReadFromJsonAsync<JsonElement>();
var jobId = job.GetProperty("id").GetString();

string status;
do
{
    await Task.Delay(1000);
    var poll = await http.GetFromJsonAsync<JsonElement>(
        $"https://api.tools.fast/compress/job/{jobId}");
    status = poll.GetProperty("status").GetString()!;
} while (status is "Queued" or "Running");

var output = await http.GetByteArrayAsync(
    $"https://api.tools.fast/compress/job/{jobId}/download");
File.WriteAllBytes("photo-compressed.jpg", output);
PowerShell 
$headers = @{ "X-Fast-Api-Key" = "fast_prod_your_key_here" }

# 1) submit
$job = Invoke-RestMethod -Method Post "https://api.tools.fast/compress" `
  -Headers $headers `
  -Form @{ file = Get-Item "photo.jpg" }

# 2) poll until complete
do {
  $status = (Invoke-RestMethod "https://api.tools.fast/compress/job/$($job.id)" `
    -Headers $headers).status
  if ($status -in "Failed", "Canceled") { throw "Job $($job.id) $status" }
  Start-Sleep -Seconds 1
} while ($status -ne "Succeeded")

# 3) download
Invoke-RestMethod "https://api.tools.fast/compress/job/$($job.id)/download" `
  -Headers $headers -OutFile "photo-compressed.jpg"

Options

The JPG compressor supports resize -- scale down images while compressing. See Options for the full resize reference.

cURL 
# compress + resize to 1080p
curl -sS -X POST "https://api.tools.fast/compress" \
  -H "X-Fast-Api-Key: $API_KEY" \
  -F "file=@photo.jpg" \
  -F 'options={"_schemaVersion":1,"resize":{"enabled":true,"preset":"1080p","mode":"pixels","value":null}}'
C# 
using var form = new MultipartFormDataContent();
form.Add(new ByteArrayContent(File.ReadAllBytes("photo.jpg")), "file", "photo.jpg");
form.Add(new StringContent(
    """{"_schemaVersion":1,"resize":{"enabled":true,"preset":"1080p","mode":"pixels","value":null}}"""),
    "options");

var response = await http.PostAsync("https://api.tools.fast/compress", form);
PowerShell 
Invoke-RestMethod -Method Post "https://api.tools.fast/compress" `
  -Headers @{ "X-Fast-Api-Key" = $Key } `
  -Form @{
    file    = Get-Item "photo.jpg"
    options = '{"_schemaVersion":1,"resize":{"enabled":true,"preset":"1080p","mode":"pixels","value":null}}'
  }

Notes

  • Output format: .jpg -- same as input.
  • EXIF metadata is preserved during compression.
  • The compressor automatically selects the optimal quality level to maximize size reduction while maintaining visual fidelity.
  • For compressing JPEG files alongside other image formats, use the Universal compressor instead.
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