## Estimate Cost

**post** `/compute/v1/predictions/structure-and-binding/estimate-cost`

Estimate the cost of a prediction without creating any resource or consuming GPU.

### Body Parameters

- `input: object { entities, binding, bonds, 3 more }`

  - `entities: array of object { chain_ids, type, value, 2 more }  or object { chain_ids, type, value, 2 more }  or object { chain_ids, type, value, 2 more }  or 2 more`

    Entities (proteins, RNA, DNA, ligands) forming the complex to predict. Order determines chain assignment.

    - `ProteinEntity = object { chain_ids, type, value, 2 more }`

      - `chain_ids: array of string`

        Chain IDs for this entity

      - `type: "protein"`

        - `"protein"`

      - `value: string`

        Amino acid sequence (one-letter codes)

      - `cyclic: optional boolean`

        Whether the sequence is cyclic

      - `modifications: optional array of object { residue_index, type, value }  or object { residue_index, type, value }`

        Post-translational modifications. Optional; defaults to an empty list when omitted.

        - `CcdModification = object { residue_index, type, value }`

          - `residue_index: number`

            0-based index of the residue to modify

          - `type: "ccd"`

            - `"ccd"`

          - `value: string`

            CCD code from RCSB PDB (e.g. 'MSE' for selenomethionine, 'SEP' for phosphoserine)

        - `SmilesModification = object { residue_index, type, value }`

          - `residue_index: number`

            0-based index of the residue to modify

          - `type: "smiles"`

            - `"smiles"`

          - `value: string`

            SMILES string for the modification

    - `RnaEntity = object { chain_ids, type, value, 2 more }`

      - `chain_ids: array of string`

        Chain IDs for this entity

      - `type: "rna"`

        - `"rna"`

      - `value: string`

        RNA nucleotide sequence (A, C, G, U, N)

      - `cyclic: optional boolean`

        Whether the sequence is cyclic

      - `modifications: optional array of object { residue_index, type, value }  or object { residue_index, type, value }`

        Chemical modifications. Optional; defaults to an empty list when omitted.

        - `CcdModification = object { residue_index, type, value }`

          - `residue_index: number`

            0-based index of the residue to modify

          - `type: "ccd"`

            - `"ccd"`

          - `value: string`

            CCD code from RCSB PDB (e.g. 'MSE' for selenomethionine, 'SEP' for phosphoserine)

        - `SmilesModification = object { residue_index, type, value }`

          - `residue_index: number`

            0-based index of the residue to modify

          - `type: "smiles"`

            - `"smiles"`

          - `value: string`

            SMILES string for the modification

    - `DnaEntity = object { chain_ids, type, value, 2 more }`

      - `chain_ids: array of string`

        Chain IDs for this entity

      - `type: "dna"`

        - `"dna"`

      - `value: string`

        DNA nucleotide sequence (A, C, G, T, N)

      - `cyclic: optional boolean`

        Whether the sequence is cyclic

      - `modifications: optional array of object { residue_index, type, value }  or object { residue_index, type, value }`

        Chemical modifications. Optional; defaults to an empty list when omitted.

        - `CcdModification = object { residue_index, type, value }`

          - `residue_index: number`

            0-based index of the residue to modify

          - `type: "ccd"`

            - `"ccd"`

          - `value: string`

            CCD code from RCSB PDB (e.g. 'MSE' for selenomethionine, 'SEP' for phosphoserine)

        - `SmilesModification = object { residue_index, type, value }`

          - `residue_index: number`

            0-based index of the residue to modify

          - `type: "smiles"`

            - `"smiles"`

          - `value: string`

            SMILES string for the modification

    - `LigandCcdEntity = object { chain_ids, type, value }`

      - `chain_ids: array of string`

        Chain IDs for this ligand

      - `type: "ligand_ccd"`

        - `"ligand_ccd"`

      - `value: string`

        CCD code (e.g., ATP, ADP)

    - `LigandSmilesEntity = object { chain_ids, type, value }`

      - `chain_ids: array of string`

        Chain IDs for this ligand

      - `type: "ligand_smiles"`

        - `"ligand_smiles"`

      - `value: string`

        SMILES string representing the ligand

  - `binding: optional object { binder_chain_id, type }  or object { binder_chain_ids, type }`

    - `LigandProteinBinding = object { binder_chain_id, type }`

      - `binder_chain_id: string`

        Chain ID of the ligand binder (must have exactly 1 copy, <50 atoms, and only ligands+proteins in entities)

      - `type: "ligand_protein_binding"`

        - `"ligand_protein_binding"`

    - `ProteinProteinBinding = object { binder_chain_ids, type }`

      - `binder_chain_ids: array of string`

        Chain IDs of the protein binders

      - `type: "protein_protein_binding"`

        - `"protein_protein_binding"`

  - `bonds: optional array of object { atom1, atom2 }`

    Bond constraints between atoms. Atom-level ligand references currently support ligand_ccd only; ligand_smiles is unsupported.

    - `atom1: object { atom_name, chain_id, type }  or object { atom_name, chain_id, residue_index, type }`

      Ligand atom reference. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

      - `LigandAtom = object { atom_name, chain_id, type }`

        Ligand atom reference. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

        - `atom_name: string`

          Standardized atom name (verifiable in CIF file on RCSB). Atom-level references to ligand_smiles entities are currently unsupported; use ligand_ccd instead.

        - `chain_id: string`

          Chain ID containing the atom

        - `type: "ligand_atom"`

          - `"ligand_atom"`

      - `PolymerAtom = object { atom_name, chain_id, residue_index, type }`

        - `atom_name: string`

          Standardized atom name (verifiable in CIF file on RCSB)

        - `chain_id: string`

          Chain ID containing the atom

        - `residue_index: number`

          0-based residue index

        - `type: "polymer_atom"`

          - `"polymer_atom"`

    - `atom2: object { atom_name, chain_id, type }  or object { atom_name, chain_id, residue_index, type }`

      Ligand atom reference. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

      - `LigandAtom = object { atom_name, chain_id, type }`

        Ligand atom reference. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

        - `atom_name: string`

          Standardized atom name (verifiable in CIF file on RCSB). Atom-level references to ligand_smiles entities are currently unsupported; use ligand_ccd instead.

        - `chain_id: string`

          Chain ID containing the atom

        - `type: "ligand_atom"`

          - `"ligand_atom"`

      - `PolymerAtom = object { atom_name, chain_id, residue_index, type }`

        - `atom_name: string`

          Standardized atom name (verifiable in CIF file on RCSB)

        - `chain_id: string`

          Chain ID containing the atom

        - `residue_index: number`

          0-based residue index

        - `type: "polymer_atom"`

          - `"polymer_atom"`

  - `constraints: optional array of object { binder_chain_id, contact_residues, max_distance_angstrom, 2 more }  or object { max_distance_angstrom, token1, token2, 2 more }`

    Structural constraints (pocket and contact). Atom-level ligand references currently support ligand_ccd only; ligand_smiles is unsupported.

    - `PocketConstraint = object { binder_chain_id, contact_residues, max_distance_angstrom, 2 more }`

      Constrains the binder to interact with specific pocket residues on the target.

      - `binder_chain_id: string`

        Chain ID of the binder molecule

      - `contact_residues: map[array of number]`

        Binding pocket residues keyed by chain ID. Each key is a chain ID (e.g. "A") and the value is an array of 0-indexed residue indices that define the pocket on that chain.

      - `max_distance_angstrom: number`

        Maximum allowed distance in Angstroms between binder and pocket residues. Typical range: 4-8 A.

      - `type: "pocket"`

        - `"pocket"`

      - `force: optional boolean`

        Whether to force the constraint

    - `ContactConstraint = object { max_distance_angstrom, token1, token2, 2 more }`

      Contact constraint between two tokens. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

      - `max_distance_angstrom: number`

        Maximum distance in Angstroms

      - `token1: object { chain_id, residue_index, type }  or object { atom_name, chain_id, type }`

        Ligand contact token. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

        - `PolymerContactToken = object { chain_id, residue_index, type }`

          - `chain_id: string`

            Chain ID

          - `residue_index: number`

            0-based residue index

          - `type: "polymer_contact"`

            - `"polymer_contact"`

        - `LigandContactToken = object { atom_name, chain_id, type }`

          Ligand contact token. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

          - `atom_name: string`

            Atom name. Atom-level references to ligand_smiles entities are currently unsupported; use ligand_ccd instead.

          - `chain_id: string`

            Chain ID

          - `type: "ligand_contact"`

            - `"ligand_contact"`

      - `token2: object { chain_id, residue_index, type }  or object { atom_name, chain_id, type }`

        Ligand contact token. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

        - `PolymerContactToken = object { chain_id, residue_index, type }`

          - `chain_id: string`

            Chain ID

          - `residue_index: number`

            0-based residue index

          - `type: "polymer_contact"`

            - `"polymer_contact"`

        - `LigandContactToken = object { atom_name, chain_id, type }`

          Ligand contact token. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

          - `atom_name: string`

            Atom name. Atom-level references to ligand_smiles entities are currently unsupported; use ligand_ccd instead.

          - `chain_id: string`

            Chain ID

          - `type: "ligand_contact"`

            - `"ligand_contact"`

      - `type: "contact"`

        - `"contact"`

      - `force: optional boolean`

        Whether to force the constraint

  - `model_options: optional object { recycling_steps, sampling_steps, step_scale }`

    - `recycling_steps: optional number`

      The number of recycling steps to use for prediction. Default is 3.

    - `sampling_steps: optional number`

      The number of sampling steps to use for prediction. Default is 200.

    - `step_scale: optional number`

      Diffusion step scale (temperature). Controls sampling diversity — higher values produce more varied structures. Default is 1.638.

  - `num_samples: optional number`

    Number of structure samples to generate

- `model: "boltz-2.1"`

  Model to use for prediction

  - `"boltz-2.1"`

- `idempotency_key: optional string`

  Client-provided key to prevent duplicate submissions on retries

- `workspace_id: optional string`

  Target workspace ID (admin keys only; ignored for workspace keys)

### Returns

- `breakdown: object { application, cost_per_unit_usd, num_units }`

  Cost breakdown for the billed application.

  - `application: "structure_and_binding" or "small_molecule_design" or "small_molecule_library_screen" or 3 more`

    - `"structure_and_binding"`

    - `"small_molecule_design"`

    - `"small_molecule_library_screen"`

    - `"protein_design"`

    - `"protein_library_screen"`

    - `"adme"`

  - `cost_per_unit_usd: string`

    Estimated cost per displayed unit as a decimal string, rounded up to 4 decimal places. This may include token-size multipliers or generation overhead; estimated_cost_usd is the authoritative total.

  - `num_units: number`

    Number of units shown for the estimate. For structure-and-binding, this is the requested number of samples. For protein and small-molecule design/screen endpoints, this is the requested number of proteins or molecules.

- `disclaimer: string`

- `estimated_cost_usd: string`

  Estimated total cost as a decimal string

### Example

```http
curl https://api.boltz.bio/compute/v1/predictions/structure-and-binding/estimate-cost \
    -H 'Content-Type: application/json' \
    -H "x-api-key: $BOLTZ_API_KEY" \
    -d '{
          "input": {
            "entities": [
              {
                "chain_ids": [
                  "string"
                ],
                "type": "protein",
                "value": "value"
              }
            ]
          },
          "model": "boltz-2.1"
        }'
```