Post

fold

/api/v1/fold

(ESM3, ESMFold2) Folds proteins. Defaults to esmfold2-fast-2026-05 if no model is given

Request

Include your API key in the Authorization header as a Bearer token.
Bodyapplication/json
modelstring | null

You may have access to additional, private models as well. These will be visible on the Rate Limits page under the Developer Console

Allowed values:esm3-open-2024-03esmfold2-fast-2026-05esmfold2-2026-05null
potential_sequence_of_concernboolean

Disclose potential sequences of concern. For approved users, such sequences will not go through additional safety filtering. Reach out if you are interested in using this.

Default:false
sequencestring | null

Input sequence to be folded.

msaMSA | null

(ESMFold2) MSA data for the query sequence.

num_loopsinteger

(ESMFold2) Number of trunk loops for iterative refinement.

Default:20Range:[0, 20]
num_sampling_stepsinteger

(ESMFold2) Diffusion ODE solver steps. Lower for speed, higher for quality.

Default:100Range:[1, 100]
lm_dropoutnumber

(ESMFold2) Dropout probability on LM pair embeddings. When > 0, dropout is applied.

Default:0.3Range:[0, 1]
lm_mask_pctnumber

(ESMFold2) Fraction of sequence residues randomly masked before the PLM backbone. If not provided, defaults to 0.1 for ESMFOLD2_FAST and 0.0 for ESMFOLD2

Default:0Range:[0, 1]
msa_max_depthinteger | null

(ESMFold2) Number of MSA rows randomly subsampled each loop. Set to null to disable (sets msa_subsample_at_inference to False).

Default:1024Range:[1, 16384]
msa_column_mask_ratenumber

(ESMFold2) Fraction of MSA columns randomly masked in non-query rows for inference-time diversity.

Default:0.1Range:[0, 1]
include_distogramboolean

(ESMFold2) Whether to include distogram predictions in the response.

Default:false
include_paeboolean

(ESMFold2) Whether to include Predicted Aligned Error (PAE) matrix in the response.

Default:false
include_pair_chains_iptmboolean

(ESMFold2) Whether to include pair-chain IPTM predictions in the response.

Default:false
include_embeddingsboolean

(ESMFold2) Whether to include sequence and pair embeddings in the response.

Default:false