diff --git a/src/app.js b/src/app.js
index a46dcec..94c8baa 100644
--- a/src/app.js
+++ b/src/app.js
@@ -13,6 +13,14 @@ import { deleteIfExists } from './storage.js';
 import { createJob, getJobByUuid } from './jobs/jobRepository.js';
 import { outputPath } from './storage.js';
 
+function isValidQuality(targetFormat, quality) {
+  if (quality === null || quality === undefined) return true;
+  if (!Number.isInteger(quality)) return false;
+  if (targetFormat === 'gif') return false;
+  if (targetFormat === 'png') return quality >= 0 && quality <= 9;
+  return quality >= 1 && quality <= 100;
+}
+
 let convertersRegistered = false;
 
 function registerAllConverters() {
@@ -73,6 +81,21 @@ export function createApp(config, pool) {
       return res.status(400).json({ error: 'targetFormats must have one entry per uploaded file' });
     }
 
+    let qualities;
+    try {
+      qualities = JSON.parse(req.body.qualities ?? '[]');
+    } catch {
+      return res.status(400).json({ error: 'qualities must be a JSON array' });
+    }
+
+    if (!Array.isArray(qualities)) {
+      return res.status(400).json({ error: 'qualities must be a JSON array' });
+    }
+
+    if (qualities.length > 0 && qualities.length !== req.files.length) {
+      return res.status(400).json({ error: 'qualities must have one entry per uploaded file, or be omitted' });
+    }
+
     const results = [];
     for (let i = 0; i < req.files.length; i += 1) {
       const file = req.files[i];
@@ -97,6 +120,16 @@ export function createApp(config, pool) {
         continue;
       }
 
+      const requestedQuality = qualities[i] ?? null;
+      if (!isValidQuality(targetFormat, requestedQuality)) {
+        await deleteIfExists(file.path);
+        results.push({
+          file: file.originalname,
+          error: `Invalid quality for target format ${targetFormat}`,
+        });
+        continue;
+      }
+
       const expiresAt = new Date(Date.now() + config.retentionHours * 3600 * 1000);
       await createJob(pool, {
         uuid,
@@ -108,6 +141,7 @@ export function createApp(config, pool) {
         inputMimeType: mime,
         inputSizeBytes: file.size,
         expiresAt,
+        quality: requestedQuality,
       });
 
       results.push({ file: file.originalname, id: uuid, status: 'pending' });
diff --git a/test/api/jobs.test.js b/test/api/jobs.test.js
index 72501f0..7622b2e 100644
--- a/test/api/jobs.test.js
+++ b/test/api/jobs.test.js
@@ -67,6 +67,61 @@ describe('POST /api/jobs', () => {
     expect(job.originalFilename).toBe('photo.png');
     expect(job.inputMimeType).toBe('image/png');
     expect(job.inputSizeBytes).toBeGreaterThan(0);
+    expect(job.quality).toBeNull();
+  });
+
+  it('creates a pending job with a quality level for a supported format', async () => {
+    const fixturePath = path.join(import.meta.dirname, '..', 'fixtures', 'sample.png');
+
+    const response = await request(app)
+      .post('/api/jobs')
+      .field('targetFormats', JSON.stringify(['jpg']))
+      .field('qualities', JSON.stringify([45]))
+      .attach('files', fixturePath, 'photo.png');
+
+    expect(response.status).toBe(201);
+    expect(response.body.jobs[0].status).toBe('pending');
+
+    const job = await getJobByUuid(pool, response.body.jobs[0].id);
+    expect(job.quality).toBe(45);
+  });
+
+  it('rejects an out-of-range quality without failing the whole batch', async () => {
+    const fixturePath = path.join(import.meta.dirname, '..', 'fixtures', 'sample.png');
+
+    const response = await request(app)
+      .post('/api/jobs')
+      .field('targetFormats', JSON.stringify(['jpg']))
+      .field('qualities', JSON.stringify([500]))
+      .attach('files', fixturePath, 'photo.png');
+
+    expect(response.status).toBe(201);
+    expect(response.body.jobs[0].error).toMatch(/Invalid quality/);
+  });
+
+  it('rejects a quality value for a format that does not support one', async () => {
+    const fixturePath = path.join(import.meta.dirname, '..', 'fixtures', 'sample.png');
+
+    const response = await request(app)
+      .post('/api/jobs')
+      .field('targetFormats', JSON.stringify(['gif']))
+      .field('qualities', JSON.stringify([50]))
+      .attach('files', fixturePath, 'photo.png');
+
+    expect(response.status).toBe(201);
+    expect(response.body.jobs[0].error).toMatch(/Invalid quality/);
+  });
+
+  it('returns 400 when qualities length does not match the number of files', async () => {
+    const fixturePath = path.join(import.meta.dirname, '..', 'fixtures', 'sample.png');
+
+    const response = await request(app)
+      .post('/api/jobs')
+      .field('targetFormats', JSON.stringify(['jpg']))
+      .field('qualities', JSON.stringify([10, 20]))
+      .attach('files', fixturePath, 'photo.png');
+
+    expect(response.status).toBe(400);
   });
 
   it('rejects a file whose content does not match its extension, without failing the whole batch', async () => {