diff --git a/codex-plonky2-circuits/Cargo.toml b/codex-plonky2-circuits/Cargo.toml
index 2502b1d..42ddfea 100644
--- a/codex-plonky2-circuits/Cargo.toml
+++ b/codex-plonky2-circuits/Cargo.toml
@@ -29,3 +29,7 @@ harness = false
 [[bench]]
 name = "prove_cells"
 harness = false
+
+[[bench]]
+name = "sample_cells"
+harness = false
diff --git a/codex-plonky2-circuits/benches/sample_cells.rs b/codex-plonky2-circuits/benches/sample_cells.rs
new file mode 100644
index 0000000..a24083d
--- /dev/null
+++ b/codex-plonky2-circuits/benches/sample_cells.rs
@@ -0,0 +1,129 @@
+use criterion::{criterion_group, criterion_main, Criterion};
+use anyhow::Result;
+use std::time::{Duration, Instant};
+use plonky2::plonk::circuit_data::{CircuitConfig, CircuitData};
+use plonky2::plonk::config::{AlgebraicHasher, GenericConfig, Hasher, PoseidonGoldilocksConfig};
+use plonky2::iop::witness::PartialWitness;
+use plonky2::hash::poseidon::PoseidonHash;
+use plonky2::field::extension::Extendable;
+use plonky2::hash::hash_types::RichField;
+use plonky2_poseidon2::poseidon2_hash::poseidon2::Poseidon2;
+use plonky2::plonk::circuit_builder::CircuitBuilder;
+use codex_plonky2_circuits::circuits::params::TESTING_SLOT_INDEX;
+use codex_plonky2_circuits::circuits::sample_cells::DatasetTreeCircuit;
+
+macro_rules! pretty_print {
+    ($($arg:tt)*) => {
+        print!("\x1b[0;36mINFO ===========>\x1b[0m ");
+        println!($($arg)*);
+    }
+}
+
+// Hash function used
+type HF = PoseidonHash;
+
+fn prepare_data<
+    F: RichField + Extendable<D> + Poseidon2,
+    C: GenericConfig<D, F = F>,
+    const D: usize,
+    H: Hasher<F> + AlgebraicHasher<F>,
+>() -> Result<(
+    DatasetTreeCircuit<F, C, D, H>,
+    usize,
+    usize,
+)> {
+    // Initialize the dataset tree with testing data
+    let mut dataset_t = DatasetTreeCircuit::<F,C,D,H>::new_for_testing();
+
+    let slot_index = TESTING_SLOT_INDEX;
+    let entropy = 123;
+
+    Ok((dataset_t, slot_index, entropy))
+}
+
+fn build_circuit<
+    F: RichField + Extendable<D> + Poseidon2,
+    C: GenericConfig<D, F = F>,
+    const D: usize,
+    H: Hasher<F> + AlgebraicHasher<F>,
+>(
+    dataset_tree: &mut DatasetTreeCircuit<F, C, D, H>,
+    slot_index: usize,
+    entropy: usize,
+    // proofs: &[MerkleProof<F, H>],
+) -> Result<(CircuitData<F, C, D>, PartialWitness<F>)>
+{
+    // Create the circuit
+    let config = CircuitConfig::standard_recursion_config();
+    let mut builder = CircuitBuilder::<F, D>::new(config);
+
+    let mut targets = dataset_tree.sample_slot_circuit(&mut builder);
+
+    // Create a PartialWitness
+    let mut pw = PartialWitness::new();
+    dataset_tree.sample_slot_assign_witness(&mut pw, &mut targets,slot_index,entropy);
+
+    // Build the circuit
+    let data = builder.build::<C>();
+
+    Ok((data, pw))
+}
+
+fn sampling_benchmark(c: &mut Criterion) {
+    let mut group = c.benchmark_group("Sampling Benchmark");
+
+    // Circuit parameters
+    const D: usize = 2;
+    type C = PoseidonGoldilocksConfig;
+    type F = <C as GenericConfig<D>>::F;
+    type H = PoseidonHash;
+
+    // Prepare the data that will be used in all steps
+    let (mut dataset_tree, slot_index, entropy) = prepare_data::<F, C, D, H>().unwrap();
+
+    // Benchmark the circuit building
+    group.bench_function("Single Cell Proof Build", |b| {
+        b.iter(|| {
+            build_circuit::<F, C, D, H>(&mut dataset_tree, slot_index, entropy).unwrap();
+        })
+    });
+
+    // Build the circuit
+    let (data, pw) = build_circuit::<F, C, D, H>(&mut dataset_tree, slot_index, entropy).unwrap();
+
+    pretty_print!(
+        "Circuit size: 2^{} gates",
+        data.common.degree_bits()
+    );
+
+    let start_time = Instant::now();
+    let proof_with_pis = data.prove(pw.clone()).unwrap();
+    println!("prove_time = {:?}", start_time.elapsed());
+
+    // Benchmark the proving time
+    group.bench_function("Single Cell Proof Prove", |b| {
+        b.iter(|| {
+            let _proof_with_pis = data.prove(pw.clone()).unwrap();
+        })
+    });
+
+    // Generate the proof
+    let proof_with_pis = data.prove(pw.clone()).unwrap();
+    let verifier_data = data.verifier_data();
+
+    pretty_print!("Proof size: {} bytes", proof_with_pis.to_bytes().len());
+
+    // Benchmark the verification time
+    group.bench_function("Single Cell Proof Verify", |b| {
+        b.iter(|| {
+            verifier_data.verify(proof_with_pis.clone()).unwrap();
+        })
+    });
+
+    group.finish();
+}
+
+criterion_group!(name = benches;
+    config = Criterion::default().sample_size(10);
+    targets = sampling_benchmark);
+criterion_main!(benches);
diff --git a/codex-plonky2-circuits/src/circuits/params.rs b/codex-plonky2-circuits/src/circuits/params.rs
index 8a0b33e..305d87e 100644
--- a/codex-plonky2-circuits/src/circuits/params.rs
+++ b/codex-plonky2-circuits/src/circuits/params.rs
@@ -4,15 +4,20 @@
 use plonky2::hash::poseidon::PoseidonHash;
 
 // constants and types used throughout the circuit
-pub const N_FIELD_ELEMS_PER_CELL: usize = 4;
+pub const N_FIELD_ELEMS_PER_CELL: usize = 256;
 pub const BOT_DEPTH: usize = 5; // block depth - depth of the block merkle tree
-pub const MAX_DEPTH: usize = 8; // depth of big tree (slot tree depth + block tree depth)
+pub const MAX_DEPTH: usize = 16; // depth of big tree (slot tree depth + block tree depth)
 pub const N_CELLS_IN_BLOCKS: usize = 1<<BOT_DEPTH; //2^BOT_DEPTH
 pub const N_BLOCKS: usize = 1<<(MAX_DEPTH - BOT_DEPTH); // 2^(MAX_DEPTH - BOT_DEPTH)
 pub const N_CELLS: usize = N_CELLS_IN_BLOCKS * N_BLOCKS;
 
-pub const DATASET_DEPTH: usize = 2;
-pub const N_SAMPLES: usize = 5;
+//the index of the slot to be sampled
+// this is fixed to speed up creating fake dataset
+// otherwise it would take lots of time
+pub const TESTING_SLOT_INDEX: usize = 2;
+
+pub const DATASET_DEPTH: usize = 5;
+pub const N_SAMPLES: usize = 10;
 
 // hash function used. this is hackish way of doing it because
 // H::Hash is not consistent with HashOut<F> and causing a lot of headache
diff --git a/codex-plonky2-circuits/src/circuits/prove_single_cell.rs b/codex-plonky2-circuits/src/circuits/prove_single_cell.rs
index 4b6ebc8..c73417d 100644
--- a/codex-plonky2-circuits/src/circuits/prove_single_cell.rs
+++ b/codex-plonky2-circuits/src/circuits/prove_single_cell.rs
@@ -91,23 +91,6 @@ impl<
             .collect::<Vec<_>>();
         // create slot tree
         let slot_tree = MerkleTree::<F, H>::new(&block_roots, zero).unwrap();
-        // let mt =
-        // MerkleTree::<F,H>{
-        //     tree: slot_tree,
-        //     block_trees,
-        //     cell_data,
-        //     cell_hash: leaves,
-        // }
-
-        // create block circuits
-        // let block_circuits = block_trees.iter()
-        //     .map(|b_tree| {
-        //         // let start = i * N_CELLS_IN_BLOCKS;
-        //         // let end = (i + 1) * N_CELLS_IN_BLOCKS;
-        //         // Self::get_block_tree(&leaves[start..end].to_vec()) // use helper function
-        //         MerkleTreeCircuit::<F,C,D,H>{ tree:b_tree.clone(), _phantom:Default::default()},
-        //     })
-        //     .collect::<Vec<_>>();
 
         Self{
             tree: MerkleTreeCircuit::<F,C,D,H>{ tree:slot_tree, _phantom:Default::default()},
@@ -124,7 +107,6 @@ impl<
     const D: usize,
     H: Hasher<F> + AlgebraicHasher<F>,
 > SlotTreeCircuit<F,C,D, H> {
-
     /// same as default but with supplied cell data
     pub fn new(cell_data: Vec<Vec<F>>) -> Self{
         let leaves: Vec<HashOut<F>> = cell_data
diff --git a/codex-plonky2-circuits/src/circuits/sample_cells.rs b/codex-plonky2-circuits/src/circuits/sample_cells.rs
index 2cbbbbd..54405cb 100644
--- a/codex-plonky2-circuits/src/circuits/sample_cells.rs
+++ b/codex-plonky2-circuits/src/circuits/sample_cells.rs
@@ -28,7 +28,7 @@ use plonky2::plonk::config::PoseidonGoldilocksConfig;
 
 use plonky2::hash::hashing::PlonkyPermutation;
 use crate::circuits::prove_single_cell::{SingleCellTargets, SlotTreeCircuit};
-use crate::circuits::params::{MAX_DEPTH, BOT_DEPTH, N_FIELD_ELEMS_PER_CELL, N_CELLS_IN_BLOCKS, N_BLOCKS, N_CELLS, HF, DATASET_DEPTH, N_SAMPLES};
+use crate::circuits::params::{MAX_DEPTH, BOT_DEPTH, N_FIELD_ELEMS_PER_CELL, N_CELLS_IN_BLOCKS, N_BLOCKS, N_CELLS, HF, DATASET_DEPTH, N_SAMPLES, TESTING_SLOT_INDEX};
 
 use crate::circuits::safe_tree_circuit::{MerkleTreeCircuit, MerkleTreeTargets};
 use crate::circuits::utils::{bits_le_padded_to_usize, calculate_cell_index_bits};
@@ -93,6 +93,45 @@ impl<
     const D: usize,
     H: Hasher<F> + AlgebraicHasher<F>,
 > DatasetTreeCircuit<F,C,D,H> {
+    /// dataset tree with fake data, for testing only
+    /// create data for only the TESTING_SLOT_INDEX in params file
+    pub fn new_for_testing() -> Self {
+        let mut slot_trees = vec![];
+        let n_slots = 1<<DATASET_DEPTH;
+        // zero hash
+        let zero = HashOut {
+            elements: [F::ZERO; 4],
+        };
+        let zero_slot = SlotTreeCircuit::<F,C,D,H>{
+            tree: MerkleTreeCircuit {
+                tree: MerkleTree::<F,H>::new(&[zero.clone()], zero.clone()).unwrap(),
+                _phantom: Default::default(),
+            },
+            block_trees: vec![],
+            cell_data: vec![],
+            cell_hash: vec![],
+        };
+        for i in 0..n_slots {
+            if(i == TESTING_SLOT_INDEX) {
+                slot_trees.push(SlotTreeCircuit::<F, C, D, H>::default());
+            }else{
+                slot_trees.push(zero_slot.clone());
+            }
+
+        }
+        // get the roots or slot trees
+        let slot_roots = slot_trees.iter()
+            .map(|t| {
+                t.tree.tree.root().unwrap()
+            })
+            .collect::<Vec<_>>();
+        let dataset_tree = MerkleTree::<F, H>::new(&slot_roots, zero).unwrap();
+        Self{
+            tree: MerkleTreeCircuit::<F,C,D,H>{ tree:dataset_tree, _phantom:Default::default()},
+            slot_trees,
+        }
+    }
+
     /// same as default but with supplied slot trees
     pub fn new(slot_trees: Vec<SlotTreeCircuit<F,C,D,H>>) -> Self{
         // get the roots or slot trees
@@ -297,4 +336,47 @@ mod tests {
 
         Ok(())
     }
+
+    #[test]
+    fn test_sample_cells_circuit_from_selected_slot() -> Result<()> {
+
+        let mut dataset_t = DatasetTreeCircuit::<F,C,D,H>::new_for_testing();
+
+        let slot_index = TESTING_SLOT_INDEX;
+        let entropy = 123;
+
+        // sanity check
+        let proof = dataset_t.sample_slot(slot_index,entropy);
+        let slot_root = dataset_t.slot_trees[slot_index].tree.tree.root().unwrap();
+        let res = dataset_t.verify_sampling(proof).unwrap();
+        assert_eq!(res, true);
+
+        // create the circuit
+        let config = CircuitConfig::standard_recursion_config();
+        let mut builder = CircuitBuilder::<F, D>::new(config);
+
+        let mut targets = dataset_t.sample_slot_circuit(&mut builder);
+
+        // create a PartialWitness and assign
+        let mut pw = PartialWitness::new();
+        dataset_t.sample_slot_assign_witness(&mut pw, &mut targets,slot_index,entropy);
+
+        // build the circuit
+        let data = builder.build::<C>();
+        println!("circuit size = {:?}", data.common.degree_bits());
+
+        // Prove the circuit with the assigned witness
+        let start_time = Instant::now();
+        let proof_with_pis = data.prove(pw)?;
+        println!("prove_time = {:?}", start_time.elapsed());
+
+        // verify the proof
+        let verifier_data = data.verifier_data();
+        assert!(
+            verifier_data.verify(proof_with_pis).is_ok(),
+            "Merkle proof verification failed"
+        );
+
+        Ok(())
+    }
 }
\ No newline at end of file