diff --git a/frontend/src/App.jsx b/frontend/src/App.jsx
index 4fec588..1124f3b 100644
--- a/frontend/src/App.jsx
+++ b/frontend/src/App.jsx
@@ -3,10 +3,25 @@ import { fetchFormats, uploadFiles } from './api.js';
 import { FileCard } from './FileCard.jsx';
 import './App.css';
 
+const DEFAULT_QUALITY = {
+  jpg: 80,
+  jpeg: 80,
+  webp: 80,
+  avif: 50,
+  tiff: 80,
+  png: 6,
+};
+
+const QUALITY_FORMATS = ['jpg', 'jpeg', 'webp', 'avif', 'tiff'];
+
 function extensionOf(fileName) {
   return fileName.split('.').pop().toLowerCase();
 }
 
+function defaultQualityFor(targetFormat) {
+  return DEFAULT_QUALITY[targetFormat] ?? null;
+}
+
 export default function App() {
   const [pendingFiles, setPendingFiles] = useState([]);
   const [submittedJobs, setSubmittedJobs] = useState([]);
@@ -16,14 +31,23 @@ export default function App() {
     const withTargets = await Promise.all(
       files.map(async (file) => {
         const targets = await fetchFormats(extensionOf(file.name));
-        return { file, targets, targetFormat: targets[0] ?? null };
+        const targetFormat = targets[0] ?? null;
+        return { file, targets, targetFormat, quality: defaultQualityFor(targetFormat) };
       })
     );
     setPendingFiles(withTargets);
   }
 
   function updateTargetFormat(index, targetFormat) {
-    setPendingFiles((current) => current.map((item, i) => (i === index ? { ...item, targetFormat } : item)));
+    setPendingFiles((current) =>
+      current.map((item, i) =>
+        i === index ? { ...item, targetFormat, quality: defaultQualityFor(targetFormat) } : item
+      )
+    );
+  }
+
+  function updateQuality(index, quality) {
+    setPendingFiles((current) => current.map((item, i) => (i === index ? { ...item, quality } : item)));
   }
 
   async function handleConvert() {
@@ -46,16 +70,64 @@ export default function App() {
               <li key={`${item.file.name}-${index}`}>
                 {item.file.name}
                 {item.targets.length > 0 ? (
-                  <select
-                    value={item.targetFormat ?? ''}
-                    onChange={(event) => updateTargetFormat(index, event.target.value)}
-                  >
-                    {item.targets.map((target) => (
-                      <option key={target} value={target}>
-                        {target}
-                      </option>
-                    ))}
-                  </select>
+                  <>
+                    <select
+                      value={item.targetFormat ?? ''}
+                      onChange={(event) => updateTargetFormat(index, event.target.value)}
+                    >
+                      {item.targets.map((target) => (
+                        <option key={target} value={target}>
+                          {target}
+                        </option>
+                      ))}
+                    </select>
+
+                    {QUALITY_FORMATS.includes(item.targetFormat) && (
+                      <label>
+                        Qualité ({item.quality})
+                        <input
+                          type="range"
+                          min="1"
+                          max="100"
+                          value={item.quality}
+                          onChange={(event) => updateQuality(index, Number(event.target.value))}
+                        />
+                      </label>
+                    )}
+
+                    {item.targetFormat === 'png' && (
+                      <label>
+                        Compression ({item.quality})
+                        <input
+                          type="range"
+                          min="0"
+                          max="9"
+                          value={item.quality}
+                          onChange={(event) => updateQuality(index, Number(event.target.value))}
+                        />
+                      </label>
+                    )}
+
+                    {item.targetFormat === 'pdf' && (
+                      <label>
+                        <input
+                          type="checkbox"
+                          checked={item.quality !== null}
+                          onChange={(event) => updateQuality(index, event.target.checked ? 90 : null)}
+                        />
+                        Compresser en JPEG
+                        {item.quality !== null && (
+                          <input
+                            type="range"
+                            min="1"
+                            max="100"
+                            value={item.quality}
+                            onChange={(event) => updateQuality(index, Number(event.target.value))}
+                          />
+                        )}
+                      </label>
+                    )}
+                  </>
                 ) : (
                   <span className="error">Format non supporté</span>
                 )}
diff --git a/frontend/src/api.js b/frontend/src/api.js
index 228f8a6..5d40d15 100644
--- a/frontend/src/api.js
+++ b/frontend/src/api.js
@@ -7,11 +7,14 @@ export async function fetchFormats(source) {
 export async function uploadFiles(items) {
   const formData = new FormData();
   const targetFormats = [];
+  const qualities = [];
   for (const item of items) {
     formData.append('files', item.file);
     targetFormats.push(item.targetFormat);
+    qualities.push(item.quality ?? null);
   }
   formData.append('targetFormats', JSON.stringify(targetFormats));
+  formData.append('qualities', JSON.stringify(qualities));
 
   const response = await fetch('/api/jobs', { method: 'POST', body: formData });
   const data = await response.json();