diff --git a/Cargo.lock b/Cargo.lock
index af129db..0733513 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -247,6 +247,12 @@ version = "1.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8c3c1a368f70d6cf7302d78f8f7093da241fb8e8807c05cc9e51a125895a6d5b"
 
+[[package]]
+name = "bitflags"
+version = "1.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
+
 [[package]]
 name = "bitflags"
 version = "2.6.0"
@@ -308,12 +314,24 @@ version = "3.16.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "79296716171880943b8470b5f8d03aa55eb2e645a4874bdbb28adb49162e012c"
 
+[[package]]
+name = "bytemuck"
+version = "1.21.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ef657dfab802224e671f5818e9a4935f9b1957ed18e58292690cc39e7a4092a3"
+
 [[package]]
 name = "byteorder"
 version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1fd0f2584146f6f2ef48085050886acf353beff7305ebd1ae69500e27c67f64b"
 
+[[package]]
+name = "byteorder-lite"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8f1fe948ff07f4bd06c30984e69f5b4899c516a3ef74f34df92a2df2ab535495"
+
 [[package]]
 name = "bytes"
 version = "1.9.0"
@@ -332,6 +350,7 @@ dependencies = [
  "diesel",
  "diesel_migrations",
  "futures",
+ "image",
  "rand",
  "serde",
  "tera",
@@ -434,6 +453,12 @@ version = "0.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f46ad14479a25103f283c0f10005961cf086d8dc42205bb44c46ac563475dca6"
 
+[[package]]
+name = "color_quant"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3d7b894f5411737b7867f4827955924d7c254fc9f4d91a6aad6b097804b1018b"
+
 [[package]]
 name = "colorchoice"
 version = "1.0.3"
@@ -652,6 +677,15 @@ version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5443807d6dff69373d433ab9ef5378ad8df50ca6298caf15de6e52e24aaf54d5"
 
+[[package]]
+name = "fdeflate"
+version = "0.3.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e6853b52649d4ac5c0bd02320cddc5ba956bdb407c4b75a2c6b75bf51500f8c"
+dependencies = [
+ "simd-adler32",
+]
+
 [[package]]
 name = "flate2"
 version = "1.0.35"
@@ -787,6 +821,16 @@ dependencies = [
  "wasi",
 ]
 
+[[package]]
+name = "gif"
+version = "0.13.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3fb2d69b19215e18bb912fa30f7ce15846e301408695e44e0ef719f1da9e19f2"
+dependencies = [
+ "color_quant",
+ "weezl",
+]
+
 [[package]]
 name = "gimli"
 version = "0.31.1"
@@ -812,7 +856,7 @@ version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0bf760ebf69878d9fd8f110c89703d90ce35095324d1f1edcb595c63945ee757"
 dependencies = [
- "bitflags",
+ "bitflags 2.6.0",
  "ignore",
  "walkdir",
 ]
@@ -970,6 +1014,22 @@ dependencies = [
  "winapi-util",
 ]
 
+[[package]]
+name = "image"
+version = "0.25.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cd6f44aed642f18953a158afeb30206f4d50da59fbc66ecb53c66488de73563b"
+dependencies = [
+ "bytemuck",
+ "byteorder-lite",
+ "color_quant",
+ "gif",
+ "num-traits",
+ "png",
+ "zune-core",
+ "zune-jpeg",
+]
+
 [[package]]
 name = "indexmap"
 version = "2.7.0"
@@ -1102,6 +1162,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4ffbe83022cedc1d264172192511ae958937694cd57ce297164951b8b3568394"
 dependencies = [
  "adler2",
+ "simd-adler32",
 ]
 
 [[package]]
@@ -1328,6 +1389,19 @@ version = "0.3.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "953ec861398dccce10c670dfeaf3ec4911ca479e9c02154b3a215178c5f566f2"
 
+[[package]]
+name = "png"
+version = "0.17.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "82151a2fc869e011c153adc57cf2789ccb8d9906ce52c0b39a6b5697749d7526"
+dependencies = [
+ "bitflags 1.3.2",
+ "crc32fast",
+ "fdeflate",
+ "flate2",
+ "miniz_oxide",
+]
+
 [[package]]
 name = "powerfmt"
 version = "0.2.0"
@@ -1408,7 +1482,7 @@ version = "0.5.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "03a862b389f93e68874fbf580b9de08dd02facb9a788ebadaf4a3fd33cf58834"
 dependencies = [
- "bitflags",
+ "bitflags 2.6.0",
 ]
 
 [[package]]
@@ -1580,6 +1654,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "simd-adler32"
+version = "0.3.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d66dc143e6b11c1eddc06d5c423cfc97062865baf299914ab64caa38182078fe"
+
 [[package]]
 name = "siphasher"
 version = "0.3.11"
@@ -1838,7 +1918,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "403fa3b783d4b626a8ad51d766ab03cb6d2dbfc46b1c5d4448395e6628dc9697"
 dependencies = [
  "async-compression",
- "bitflags",
+ "bitflags 2.6.0",
  "bytes",
  "futures-core",
  "futures-util",
@@ -2096,6 +2176,12 @@ version = "0.2.99"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "943aab3fdaaa029a6e0271b35ea10b72b943135afe9bffca82384098ad0e06a6"
 
+[[package]]
+name = "weezl"
+version = "0.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "53a85b86a771b1c87058196170769dd264f66c0782acf1ae6cc51bfd64b39082"
+
 [[package]]
 name = "winapi"
 version = "0.3.9"
@@ -2247,3 +2333,18 @@ dependencies = [
  "quote",
  "syn",
 ]
+
+[[package]]
+name = "zune-core"
+version = "0.4.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3f423a2c17029964870cfaabb1f13dfab7d092a62a29a89264f4d36990ca414a"
+
+[[package]]
+name = "zune-jpeg"
+version = "0.4.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "99a5bab8d7dedf81405c4bb1f2b83ea057643d9cb28778cea9eecddeedd2e028"
+dependencies = [
+ "zune-core",
+]
diff --git a/Cargo.toml b/Cargo.toml
index da5ef6e..0efdb25 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -16,6 +16,7 @@ clap = { version = "4.5.26", features = ["derive", "env"] }
 diesel = { version = "2.2.6", features = ["sqlite", "returning_clauses_for_sqlite_3_35", "r2d2", "chrono"] }
 diesel_migrations = { version = "2.2.0", features = ["sqlite"] }
 futures = "0.3.31"
+image = { version = "0.25.5", default-features = false, features = ["gif", "jpeg", "png"] }
 rand = "0.8.5"
 # this dependency is needed soly because the r2d2_sqlite crate doesn't export
 # the 'chrono' feature flag
diff --git a/migrations/2025-01-16-195902_images/up.sql b/migrations/2025-01-16-195902_images/up.sql
index 191ca73..28a02d8 100644
--- a/migrations/2025-01-16-195902_images/up.sql
+++ b/migrations/2025-01-16-195902_images/up.sql
@@ -5,5 +5,6 @@ create table images (
         -- Keep entries in the database so the files can be removed later
         on delete set null,
     date_taken date not null,
+    mime_type text not null,
     note text
 );
diff --git a/src/db/models/image.rs b/src/db/models/image.rs
index 592c600..48e2825 100644
--- a/src/db/models/image.rs
+++ b/src/db/models/image.rs
@@ -11,6 +11,7 @@ pub struct Image {
     pub id: i32,
     pub plant_id: i32,
     pub date_taken: NaiveDate,
+    pub mime_type: String,
     pub note: Option<String>,
 }
 
@@ -20,14 +21,21 @@ pub struct Image {
 pub struct NewImage {
     plant_id: i32,
     date_taken: NaiveDate,
+    mime_type: String,
     note: Option<String>,
 }
 
 impl NewImage {
-    pub fn new(plant_id: i32, date_taken: NaiveDate, note: Option<String>) -> Self {
+    pub fn new(
+        plant_id: i32,
+        date_taken: NaiveDate,
+        mime_type: String,
+        note: Option<String>,
+    ) -> Self {
         Self {
             plant_id,
             date_taken,
+            mime_type,
             note,
         }
     }
diff --git a/src/db/schema.rs b/src/db/schema.rs
index 71db738..4ae1375 100644
--- a/src/db/schema.rs
+++ b/src/db/schema.rs
@@ -15,6 +15,7 @@ diesel::table! {
         id -> Integer,
         plant_id -> Integer,
         date_taken -> Date,
+        mime_type -> Text,
         note -> Nullable<Text>,
     }
 }
diff --git a/src/main.rs b/src/main.rs
index ac6a06e..5536a58 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -10,6 +10,7 @@ use std::{
 
 use clap::Parser;
 use tera::Tera;
+use tokio::sync::Mutex;
 use tower_http::compression::CompressionLayer;
 
 use cli::UserCmd;
@@ -17,12 +18,26 @@ use db::DbError;
 
 const DB_FILENAME: &str = "db.sqlite3";
 const IMG_DIR: &str = "imgs";
+const TMP_DIR: &str = "tmp";
 
 #[derive(Clone)]
 pub struct Context {
     pool: db::DbPool,
     tera: Arc<Tera>,
     data_dir: PathBuf,
+    tmp_dir_counter: Arc<Mutex<u16>>,
+}
+
+impl Context {
+    pub async fn tmp_file_path(&self) -> PathBuf {
+        let mut guard = self.tmp_dir_counter.lock().await;
+
+        let path = self.data_dir.join(TMP_DIR).join(guard.to_string());
+
+        *guard = guard.wrapping_add(1);
+
+        path
+    }
 }
 
 fn run_user_cli(data_dir: impl AsRef<Path>, cmd: UserCmd) -> Result<(), DbError> {
@@ -69,6 +84,10 @@ async fn main() {
                 fs::create_dir(args.data_dir.join(IMG_DIR)).unwrap();
             }
 
+            if !fs::exists(args.data_dir.join(TMP_DIR)).unwrap() {
+                fs::create_dir(args.data_dir.join(TMP_DIR)).unwrap();
+            }
+
             let pool = db::initialize_db(args.data_dir.join(DB_FILENAME), true).unwrap();
 
             let tera =
@@ -78,6 +97,7 @@ async fn main() {
                 pool,
                 tera: Arc::new(tera),
                 data_dir: args.data_dir.clone(),
+                tmp_dir_counter: Arc::new(Mutex::new(0)),
             };
             let app = server::app(ctx, &args.static_dir)
                 .layer(CompressionLayer::new().br(true).gzip(true));
diff --git a/src/server/error.rs b/src/server/error.rs
index eb5f3a8..79370ac 100644
--- a/src/server/error.rs
+++ b/src/server/error.rs
@@ -83,6 +83,15 @@ impl From<std::io::Error> for AppError {
     }
 }
 
+impl From<image::ImageError> for AppError {
+    fn from(value: image::ImageError) -> Self {
+        match value {
+            image::ImageError::IoError(err) => Self::IO(err),
+            _ => Self::BadRequest,
+        }
+    }
+}
+
 impl IntoResponse for AppError {
     fn into_response(self) -> axum::response::Response {
         match self {
diff --git a/src/server/images.rs b/src/server/images.rs
index 20b7c0e..414b931 100644
--- a/src/server/images.rs
+++ b/src/server/images.rs
@@ -1,18 +1,30 @@
 use axum::{
-    extract::{multipart::Field, Multipart, State},
+    extract::{DefaultBodyLimit, Multipart, State},
+    handler::Handler,
     response::Html,
     routing::post,
     Router,
 };
 use chrono::NaiveDate;
 use futures::TryStreamExt;
+use image::{codecs::jpeg::JpegEncoder, ImageReader};
 use tokio_util::io::StreamReader;
 
+use std::{io::BufWriter, path::PathBuf};
+
 use super::error::AppError;
-use crate::db::NewImage;
+use crate::{
+    db::{Image, NewImage},
+    IMG_DIR,
+};
+
+const THUMBNAIL_EXT: &str = "thumb";
 
 pub fn app() -> axum::Router<crate::Context> {
-    Router::new().route("/", post(post_image))
+    Router::new().route(
+        "/",
+        post(post_image.layer(DefaultBodyLimit::max(1024 * 1024 * 20))),
+    )
 }
 
 async fn post_image(
@@ -23,6 +35,9 @@ async fn post_image(
     let mut date_taken: Option<NaiveDate> = None;
     let mut note: Option<String> = None;
 
+    let mut img_paths: Option<(PathBuf, PathBuf)> = None;
+    let mut mime_type: Option<&'static str> = None;
+
     while let Some(field) = mt.next_field().await? {
         match field.name() {
             Some("plant_id") => {
@@ -47,15 +62,21 @@ async fn post_image(
                 note = Some(field.text().await?);
             }
             Some("image") => {
-                // These fields are required to be provided before the image field (note is
-                // optional)
-                if plant_id.is_none() || date_taken.is_none() {
-                    return Err(AppError::BadRequest);
-                }
+                let path = ctx.tmp_file_path().await;
 
-                receive_image(ctx, plant_id.unwrap(), date_taken.unwrap(), note, field).await?;
+                let mut f = tokio::fs::File::create(&path).await?;
+                let mut r = StreamReader::new(field.map_err(std::io::Error::other));
 
-                return Ok(Html(String::new()));
+                tokio::io::copy(&mut r, &mut f).await?;
+
+                let jpeg_path = ctx.tmp_file_path().await;
+                img_paths = Some((path.clone(), jpeg_path.clone()));
+
+                mime_type = Some(
+                    tokio::task::spawn_blocking(move || process_image(path, jpeg_path))
+                        .await
+                        .unwrap()?,
+                );
             }
             _ => {
                 return Err(AppError::BadRequest);
@@ -63,31 +84,47 @@ async fn post_image(
         }
     }
 
-    Err(AppError::BadRequest)
+    if let (Some(plant_id), Some(date_taken), Some((img_path, jpeg_path)), Some(mime_type)) =
+        (plant_id, date_taken, img_paths, mime_type)
+    {
+        let image = NewImage::new(plant_id, date_taken, mime_type.to_string(), note);
+        let image =
+            tokio::task::spawn_blocking(move || insert_image(&ctx, image, img_path, jpeg_path))
+                .await
+                .unwrap()?;
+
+        Ok(Html(String::new()))
+    } else {
+        Err(AppError::BadRequest)
+    }
 }
 
-async fn receive_image<'a>(
-    ctx: crate::Context,
-    plant_id: i32,
-    date_taken: NaiveDate,
-    note: Option<String>,
-    field: Field<'a>,
-) -> super::Result<()> {
-    let image = tokio::task::spawn_blocking(move || {
-        NewImage::new(plant_id, date_taken, note).insert(&ctx.pool)
-    })
-    .await
-    .unwrap()?;
+fn process_image(path: PathBuf, jpg_path: PathBuf) -> super::Result<&'static str> {
+    let reader = ImageReader::open(path)?.with_guessed_format()?;
+    let mime_type = reader.format().ok_or(AppError::BadRequest)?.to_mime_type();
 
-    let mut r = StreamReader::new(field.map_err(std::io::Error::other));
-    let mut f = tokio::fs::File::create(
-        ctx.data_dir
-            .join(crate::IMG_DIR)
-            .join(image.id.to_string())
-            .with_extension("png"),
-    )
-    .await?;
-    tokio::io::copy(&mut r, &mut f).await?;
+    // Decode image and resize to fit into 720 x 720 square
+    let img = reader.decode()?.thumbnail(720, 720);
 
-    Ok(())
+    // Write image as compressed JPEG
+    let jpeg_f = BufWriter::new(std::fs::File::create(jpg_path)?);
+    let encoder = JpegEncoder::new_with_quality(jpeg_f, 60);
+    img.write_with_encoder(encoder)?;
+
+    Ok(mime_type)
+}
+
+fn insert_image(
+    ctx: &crate::Context,
+    image: NewImage,
+    img_path: PathBuf,
+    jpeg_path: PathBuf,
+) -> super::Result<Image> {
+    let image = image.insert(&ctx.pool)?;
+
+    let dest_path = ctx.data_dir.join(IMG_DIR).join(image.id.to_string());
+    std::fs::rename(img_path, &dest_path)?;
+    std::fs::rename(jpeg_path, dest_path.with_extension(THUMBNAIL_EXT))?;
+
+    Ok(image)
 }