diff --git a/Cargo.lock b/Cargo.lock
index 3a536075cf..9349e7f0c8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -68,6 +68,21 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "alloc-no-stdlib"
+version = "2.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cc7bb162ec39d46ab1ca8c77bf72e890535becd1751bb45f64c597edb4c8c6b3"
+
+[[package]]
+name = "alloc-stdlib"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "94fb8275041c72129eb51b7d0322c29b8387a0386127718b096429201a5d6ece"
+dependencies = [
+ "alloc-no-stdlib",
+]
+
 [[package]]
 name = "allocator-api2"
 version = "0.2.16"
@@ -653,6 +668,7 @@ dependencies = [
  "astria-merkle",
  "base64 0.21.7",
  "base64-serde",
+ "brotli",
  "bytes",
  "celestia-tendermint",
  "ed25519-consensus",
@@ -1337,6 +1353,27 @@ dependencies = [
  "syn_derive",
 ]
 
+[[package]]
+name = "brotli"
+version = "5.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "19483b140a7ac7174d34b5a581b406c64f84da5409d3e09cf4fff604f9270e67"
+dependencies = [
+ "alloc-no-stdlib",
+ "alloc-stdlib",
+ "brotli-decompressor",
+]
+
+[[package]]
+name = "brotli-decompressor"
+version = "4.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6221fe77a248b9117d431ad93761222e1cf8ff282d9d1d5d9f53d6299a1cf76"
+dependencies = [
+ "alloc-no-stdlib",
+ "alloc-stdlib",
+]
+
 [[package]]
 name = "bs58"
 version = "0.5.1"
diff --git a/crates/astria-conductor/Cargo.toml b/crates/astria-conductor/Cargo.toml
index e3a130bbca..6a1770b59b 100644
--- a/crates/astria-conductor/Cargo.toml
+++ b/crates/astria-conductor/Cargo.toml
@@ -13,7 +13,11 @@ name = "astria-conductor"
 
 [dependencies]
 astria-build-info = { path = "../astria-build-info", features = ["runtime"] }
-astria-core = { path = "../astria-core", features = ["client", "serde"] }
+astria-core = { path = "../astria-core", features = [
+  "client",
+  "serde",
+  "brotli",
+] }
 astria-eyre = { path = "../astria-eyre" }
 celestia-client = { package = "astria-celestia-client", path = "../astria-celestia-client" }
 config = { package = "astria-config", path = "../astria-config" }
@@ -56,7 +60,11 @@ tracing-futures = { version = "0.2.5", features = ["futures-03"] }
 moka = { version = "0.12.5", features = ["future"] }
 
 [dev-dependencies]
-astria-core = { path = "../astria-core", features = ["server", "test-utils"] }
+astria-core = { path = "../astria-core", features = [
+  "server",
+  "test-utils",
+  "brotli",
+] }
 astria-grpc-mock = { path = "../astria-grpc-mock" }
 config = { package = "astria-config", path = "../astria-config", features = [
   "tests",
diff --git a/crates/astria-conductor/src/celestia/convert.rs b/crates/astria-conductor/src/celestia/convert.rs
index 10b7ee7462..76e1e03984 100644
--- a/crates/astria-conductor/src/celestia/convert.rs
+++ b/crates/astria-conductor/src/celestia/convert.rs
@@ -1,3 +1,4 @@
+use astria_core::brotli::decompress_bytes;
 use celestia_client::{
     celestia_types::{
         nmt::Namespace,
@@ -97,7 +98,15 @@ impl ConvertedBlobs {
 
 fn convert_header(blob: &Blob) -> Option<CelestiaSequencerBlob> {
     use astria_core::generated::sequencerblock::v1alpha1::CelestiaSequencerBlob as ProtoType;
-    let raw = ProtoType::decode(&*blob.data)
+    let data = decompress_bytes(&blob.data)
+        .inspect_err(|err| {
+            info!(
+                error = err as &StdError,
+                "failed decompressing blob data; dropping the blob",
+            );
+        })
+        .ok()?;
+    let raw = ProtoType::decode(&*data)
         .inspect_err(|err| {
             info!(
                 error = err as &StdError,
@@ -118,7 +127,15 @@ fn convert_header(blob: &Blob) -> Option<CelestiaSequencerBlob> {
 
 fn convert_rollup(blob: &Blob) -> Option<CelestiaRollupBlob> {
     use astria_core::generated::sequencerblock::v1alpha1::CelestiaRollupBlob as ProtoType;
-    let raw_blob = ProtoType::decode(&*blob.data)
+    let data = decompress_bytes(&blob.data)
+        .inspect_err(|err| {
+            info!(
+                error = err as &StdError,
+                "failed decompressing rollup blob data; dropping the blob",
+            );
+        })
+        .ok()?;
+    let raw_blob = ProtoType::decode(&*data)
         .inspect_err(|err| {
             info!(
                 error = err as &StdError,
diff --git a/crates/astria-conductor/tests/blackbox/helpers/mod.rs b/crates/astria-conductor/tests/blackbox/helpers/mod.rs
index f1ecf4989a..032693b2a8 100644
--- a/crates/astria-conductor/tests/blackbox/helpers/mod.rs
+++ b/crates/astria-conductor/tests/blackbox/helpers/mod.rs
@@ -6,6 +6,7 @@ use astria_conductor::{
     Config,
 };
 use astria_core::{
+    brotli::compress_bytes,
     generated::{
         execution::v1alpha2::{
             Block,
@@ -32,6 +33,7 @@ use sequencer_client::{
 #[macro_use]
 mod macros;
 mod mock_grpc;
+use astria_eyre;
 pub use mock_grpc::MockGrpc;
 use serde_json::json;
 use tokio::task::JoinHandle;
@@ -476,17 +478,21 @@ pub struct Blobs {
 pub fn make_blobs(height: u32) -> Blobs {
     let (head, tail) = make_sequencer_block(height).into_celestia_blobs();
 
+    let raw_header = ::prost::Message::encode_to_vec(&head.into_raw());
+    let head_compressed = compress_bytes(&raw_header).unwrap();
     let header = ::celestia_client::celestia_types::Blob::new(
         ::celestia_client::celestia_namespace_v0_from_bytes(crate::SEQUENCER_CHAIN_ID.as_bytes()),
-        ::prost::Message::encode_to_vec(&head.into_raw()),
+        head_compressed,
     )
     .unwrap();
 
     let mut rollup = Vec::new();
     for elem in tail {
+        let raw_rollup = ::prost::Message::encode_to_vec(&elem.into_raw());
+        let rollup_compressed = compress_bytes(&raw_rollup).unwrap();
         let blob = ::celestia_client::celestia_types::Blob::new(
             ::celestia_client::celestia_namespace_v0_from_rollup_id(crate::ROLLUP_ID),
-            ::prost::Message::encode_to_vec(&elem.into_raw()),
+            rollup_compressed,
         )
         .unwrap();
         rollup.push(blob);
diff --git a/crates/astria-core/Cargo.toml b/crates/astria-core/Cargo.toml
index f3be1f5daf..856e11ca42 100644
--- a/crates/astria-core/Cargo.toml
+++ b/crates/astria-core/Cargo.toml
@@ -16,6 +16,7 @@ keywords = ["astria", "grpc", "rpc", "blockchain", "execution", "protobuf"]
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+brotli = { version = "5.0.0", optional = true }
 pbjson = { version = "0.6.0", optional = true }
 
 merkle = { package = "astria-merkle", path = "../astria-merkle" }
@@ -46,6 +47,7 @@ serde = ["dep:serde", "dep:pbjson", "dep:base64-serde"]
 server = ["dep:tonic"]
 test-utils = ["dep:rand"]
 base64-serde = ["dep:base64-serde"]
+brotli = ["dep:brotli"]
 
 [dev-dependencies]
 astria-core = { path = ".", features = ["serde"] }
diff --git a/crates/astria-core/src/brotli.rs b/crates/astria-core/src/brotli.rs
new file mode 100644
index 0000000000..211e75bc4d
--- /dev/null
+++ b/crates/astria-core/src/brotli.rs
@@ -0,0 +1,53 @@
+use std::io::Write as _;
+
+use brotli::{
+    enc::BrotliEncoderParams,
+    CompressorWriter,
+    DecompressorWriter,
+};
+
+const BROTLI_BUFFER_SIZE: usize = 4096;
+
+/// Decompresses the given bytes using the Brotli algorithm.
+///
+/// Returns the decompressed bytes.
+///
+/// # Errors
+///
+/// Returns an error if the decompression fails.
+pub fn decompress_bytes(data: &[u8]) -> Result<Vec<u8>, std::io::Error> {
+    // Header blobs are small and occur frequently with low compression, capacity based on expecting
+    // those to be the most common case and reduce allocations.
+    let mut output = Vec::with_capacity(data.len());
+    {
+        let mut decompressor = DecompressorWriter::new(&mut output, BROTLI_BUFFER_SIZE);
+        decompressor.write_all(data)?;
+    }
+
+    Ok(output)
+}
+
+/// Compresses the given bytes using the Brotli algorithm at setting 5.
+///
+/// Returns the compressed bytes.
+///
+/// # Errors
+///
+/// Returns an error if the compression fails.
+pub fn compress_bytes(data: &[u8]) -> Result<Vec<u8>, std::io::Error> {
+    let compression_params = BrotliEncoderParams {
+        quality: 5,
+        size_hint: data.len(),
+        ..Default::default()
+    };
+    // Header blobs are small and occur frequently with low compression, capacity based on expecting
+    // those to be the most common case and reduce allocations.
+    let mut output = Vec::with_capacity(data.len());
+    {
+        let mut compressor =
+            CompressorWriter::with_params(&mut output, BROTLI_BUFFER_SIZE, &compression_params);
+        compressor.write_all(data)?;
+    }
+
+    Ok(output)
+}
diff --git a/crates/astria-core/src/lib.rs b/crates/astria-core/src/lib.rs
index cc1f875ef9..81bef23801 100644
--- a/crates/astria-core/src/lib.rs
+++ b/crates/astria-core/src/lib.rs
@@ -11,6 +11,8 @@ pub mod primitive;
 pub mod protocol;
 pub mod sequencerblock;
 
+#[cfg(feature = "brotli")]
+pub mod brotli;
 #[cfg(feature = "serde")]
 pub(crate) mod serde;
 
diff --git a/crates/astria-sequencer-relayer/Cargo.toml b/crates/astria-sequencer-relayer/Cargo.toml
index d8ef64fda9..920c6d6b36 100644
--- a/crates/astria-sequencer-relayer/Cargo.toml
+++ b/crates/astria-sequencer-relayer/Cargo.toml
@@ -47,7 +47,11 @@ tokio-util = { workspace = true }
 tonic = { workspace = true }
 
 astria-build-info = { path = "../astria-build-info", features = ["runtime"] }
-astria-core = { path = "../astria-core", features = ["client", "serde"] }
+astria-core = { path = "../astria-core", features = [
+  "client",
+  "serde",
+  "brotli",
+] }
 astria-eyre = { path = "../astria-eyre" }
 celestia-client = { package = "astria-celestia-client", path = "../astria-celestia-client" }
 config = { package = "astria-config", path = "../astria-config" }
diff --git a/crates/astria-sequencer-relayer/src/metrics_init.rs b/crates/astria-sequencer-relayer/src/metrics_init.rs
index 2b47666c6a..a07dc3f598 100644
--- a/crates/astria-sequencer-relayer/src/metrics_init.rs
+++ b/crates/astria-sequencer-relayer/src/metrics_init.rs
@@ -61,6 +61,18 @@ pub fn register() {
         Unit::Seconds,
         "The time it takes to submit a blob to Celestia"
     );
+
+    describe_gauge!(
+        TOTAL_BLOB_DATA_SIZE_FOR_ASTRIA_BLOCK,
+        Unit::Bytes,
+        "The size of all compressed data for all `blob.data`s in an Astria block"
+    );
+
+    describe_gauge!(
+        COMPRESSION_RATIO_FOR_ASTRIA_BLOCK,
+        Unit::Count,
+        "Ratio of uncompressed:compressed data size for all `blob.data`s in an Astria block"
+    );
 }
 
 // We configure buckets for manually, in order to ensure Prometheus metrics are structured as a
@@ -96,3 +108,12 @@ pub const SEQUENCER_HEIGHT_FETCH_FAILURE_COUNT: &str = concat!(
     env!("CARGO_CRATE_NAME"),
     "_sequencer_height_fetch_failure_count",
 );
+
+pub const TOTAL_BLOB_DATA_SIZE_FOR_ASTRIA_BLOCK: &str = concat!(
+    env!("CARGO_CRATE_NAME"),
+    "_total_blob_data_size_for_astria_block"
+);
+pub const COMPRESSION_RATIO_FOR_ASTRIA_BLOCK: &str = concat!(
+    env!("CARGO_CRATE_NAME"),
+    "_compression_ratio_for_astria_block"
+);
diff --git a/crates/astria-sequencer-relayer/src/relayer/write/conversion.rs b/crates/astria-sequencer-relayer/src/relayer/write/conversion.rs
index f1bc80d1e0..db6dafae57 100644
--- a/crates/astria-sequencer-relayer/src/relayer/write/conversion.rs
+++ b/crates/astria-sequencer-relayer/src/relayer/write/conversion.rs
@@ -1,4 +1,7 @@
-use astria_core::primitive::v1::RollupId;
+use astria_core::{
+    brotli::compress_bytes,
+    primitive::v1::RollupId,
+};
 use astria_eyre::eyre::{
     self,
     WrapErr as _,
@@ -10,6 +13,9 @@ use celestia_client::celestia_types::{
 use prost::Message as _;
 use sequencer_client::SequencerBlock;
 use tendermint::block::Height as SequencerHeight;
+use tracing::debug;
+
+use crate::metrics_init;
 
 // allow: the signature is dictated by the `serde(serialize_with = ...)` attribute.
 #[allow(clippy::trivially_copy_pass_by_ref)]
@@ -54,6 +60,8 @@ pub(super) struct Converted {
 
 pub(super) fn convert(block: SequencerBlock) -> eyre::Result<Converted> {
     let sequencer_height = block.height();
+    let mut total_data_uncompressed_size = 0;
+    let mut total_data_compressed_size = 0;
 
     let (sequencer_blob, rollup_blobs) = block.into_celestia_blobs();
     // Allocate extra space: one blob for the sequencer blob "header",
@@ -62,12 +70,14 @@ pub(super) fn convert(block: SequencerBlock) -> eyre::Result<Converted> {
     let sequencer_namespace = celestia_client::celestia_namespace_v0_from_str(
         sequencer_blob.header().chain_id().as_str(),
     );
+    let sequencer_blob_raw = sequencer_blob.into_raw().encode_to_vec();
+    total_data_uncompressed_size += sequencer_blob_raw.len();
+    let compressed_sequencer_blob_raw =
+        compress_bytes(&sequencer_blob_raw).wrap_err("failed compressing sequencer blob")?;
+    total_data_compressed_size += compressed_sequencer_blob_raw.len();
 
-    let header_blob = Blob::new(
-        sequencer_namespace,
-        sequencer_blob.into_raw().encode_to_vec(),
-    )
-    .wrap_err("failed creating head Celestia blob")?;
+    let header_blob = Blob::new(sequencer_namespace, compressed_sequencer_blob_raw)
+        .wrap_err("failed creating head Celestia blob")?;
     blobs.push(header_blob);
     let mut rollups = Vec::new();
     for blob in rollup_blobs {
@@ -78,11 +88,31 @@ pub(super) fn convert(block: SequencerBlock) -> eyre::Result<Converted> {
             celestia_namespace: namespace,
             sequencer_rollup_id: blob.rollup_id(),
         };
-        let blob = Blob::new(namespace, blob.into_raw().encode_to_vec())
+        let raw_blob = blob.into_raw().encode_to_vec();
+        total_data_uncompressed_size += raw_blob.len();
+        let compressed_blob = compress_bytes(&raw_blob)
+            .wrap_err_with(|| format!("failed compressing rollup `{rollup_id}`"))?;
+        total_data_compressed_size += compressed_blob.len();
+        let blob = Blob::new(namespace, compressed_blob)
             .wrap_err_with(|| format!("failed creating blob for rollup `{rollup_id}`"))?;
         blobs.push(blob);
         rollups.push(info);
     }
+
+    // gauges require f64, it's okay if the metrics get messed up by overflow or precision loss
+    #[allow(clippy::cast_precision_loss)]
+    let compression_ratio = total_data_uncompressed_size as f64 / total_data_compressed_size as f64;
+    debug!(
+        sequencer_height = %sequencer_height,
+        total_data_compressed_size = total_data_compressed_size,
+        compression_ratio = compression_ratio,
+        "converted blocks into blobs with compressed data",
+    );
+    #[allow(clippy::cast_precision_loss)]
+    metrics::gauge!(metrics_init::TOTAL_BLOB_DATA_SIZE_FOR_ASTRIA_BLOCK)
+        .set(total_data_compressed_size as f64);
+    metrics::gauge!(metrics_init::COMPRESSION_RATIO_FOR_ASTRIA_BLOCK).set(compression_ratio);
+
     Ok(Converted {
         blobs,
         info: ConversionInfo {