Reference implementation and checkpoint configuration deepseek-ai/DeepSeek-V4.1-Flash @ 2cba9e4 · parameter count checked against the checkpoint’s tensor headers · text model only · How to read

in
Raw text
out
LL [B, T, 129280]
parameters
748,494,684,784 in all
mode
prefill, empty cache
state
normalized ID cache: rows 0…T−1 written, of 65,536, then read by the hashes in the same call
Parameters

748,494,684,784 parameters in DeepSeek V4.1

Exact model ownership reconciliation
ComponentCalculationParameters
Token embedding129,280×5,120129{,}280 \times 5{,}120661,913,600
Layers747,170,852,464 across its components747,170,852,464
Final RMSNorm5,1205{,}1205,120
Vocabulary projection5,120×129,2805{,}120 \times 129{,}280661,913,600
Model total748,494,684,784

Derived exact parameter total: 748,494,684,784. Sources contains the pinned configuration and implementation used for this derivation.

Derived from the pinned reference implementation and configuration; equal to the element counts of the checkpoint’s own tensors on the text path. The quantisation scales, the vision encoder and the DSpark blocks are not counted.

Sources

Direct evidence

The reference configuration: 40 layers of width 5,120, 64 heads of 512 features with a 64-feature rotary part, a 1,280-feature query latent, a grouped output of 8 groups at rank 1,024, a window of 128, the per-layer compression ratios and the two source lists, the indexer and its candidate stage, hyper-connections of 4 streams, 384 routed experts of which 6 are used with 1 shared, Engram before layers 1 and 14, and three DSpark blocks.

config · deepseek-ai/DeepSeek-V4.1-Flash / inference/config.json
Pinned revision 2cba9e42aa02 ↗ · lines 1–66

Read code excerpt
{
    "vocab_size": 129280,
    "dim": 5120,
    "moe_inter_dim": 2304,
    "n_layers": 40,
    "n_mtp_layers": 3,
    "dspark_block_size": 5,
    "dspark_noise_token_id": 128799,
    "dspark_target_layer_ids": [37, 38, 39],
    "dspark_markov_rank": 256,
    "dspark_n_routed_experts": 128,
    "dspark_n_activated_experts": 3,
    "n_heads": 64,
    "n_routed_experts": 384,
    "n_shared_experts": 1,
    "n_activated_experts": 6,
    "score_func": "sqrtsoftplus",
    "route_scale": 1.5,
    "swiglu_limit": 10.0,
    "q_lora_rank": 1280,
    "head_dim": 512,
    "rope_head_dim": 64,
    "norm_eps": 1e-20,
    "o_groups": 8,
    "o_lora_rank": 1024,
    "window_size": 128,
    "kv_source_layers": [2, 8, 14, 20],
    "index_source_layers": [2, 8, 14, 20, 24, 28, 32, 36],
    "original_seq_len": 65536,
    "rope_theta": 10000,
    "rope_factor": 16,
    "beta_fast": 32,
    "beta_slow": 1,
    "index_n_heads": 32,
    "index_head_dim": 128,
    "index_topk": 512,
    "candidate_source_layer": 20,
    "candidate_topk_blocks": 2048,
    "candidate_block_size": 8,
    "hc_mult": 4,
    "hc_sinkhorn_iters": 20,
    "hc_eps": 1e-06,
    "engram_layer_ids": [1, 14],
    "engram_vocab_size": 16000000,
    "engram_num_embeddings": [384006168, 384016682],
    "engram_max_ngram_size": 4,
    "engram_pad_id": 2,
    "engram_compressed_vocab_size": 99092,
    "dtype": "fp8",
    "expert_dtype": "fp4",
    "compress_rope_theta": 160000,
    "compress_ratios": [0, 0, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0],
    "vision_n_layers": 32,
    "vision_dim": 1024,
    "vision_n_heads": 16,
    "vision_inter_dim": 2816,
    "vision_patch_size": 14,
    "vision_downsample_ratio": 3,
    "vision_max_n_token": 1024,
    "vision_min_pixels": 295936,
    "vision_max_wh_ratio": null,
    "image_token_id": 129264,
    "engram_n_heads": 8,
    "engram_head_dim": 256,
    "vision_rope_theta": 10000
}

Direct evidence

The model owns the embedding, 40 blocks, the final norm and the head, with the n-gram hashing and, when configured, a vision encoder.

transformer-init · deepseek-ai/DeepSeek-V4.1-Flash / inference/model.py
Pinned revision 2cba9e42aa02 ↗ · lines 1183–1223

Read code excerpt
class Transformer(nn.Module):
    """DeepSeek-V4.1: embed -> expand to hc_mult copies -> blocks -> collapse -> logits. Building
    this sets the globals at the top of the file. The tokenizer only feeds the engram token map."""

    def __init__(self, args: ModelArgs, tokenizer=None):
        global world_size, rank, default_dtype
        world_size = dist.get_world_size() if dist.is_initialized() else 1
        rank = dist.get_rank() if dist.is_initialized() else 0
        default_dtype = torch.float8_e4m3fn if args.dtype == "fp8" else torch.bfloat16
        super().__init__()
        self.max_seq_len = args.max_seq_len
        self.temperature = args.temperature
        self.norm_eps = args.norm_eps
        self.hc_eps = args.hc_eps
        self.engram_layout = EngramLayout.from_args(args)
        self.engram_hash = (
            NgramHashState(args, self.engram_layout, tokenizer) if self.engram_layout is not None else None
        )
        self.embed = ParallelEmbedding(args.vocab_size, args.dim)
        self.layers = torch.nn.ModuleList()
        for layer_id in range(args.n_layers):
            self.layers.append(Block(layer_id, args, self.engram_layout))
        self.norm = RMSNorm(args.dim, self.norm_eps)
        self.head = ParallelHead(args.vocab_size, args.dim, self.norm_eps, self.hc_eps)
        self.mtp = torch.nn.ModuleList()
        self.target_layer_ids = args.dspark_target_layer_ids
        if args.dspark_block_size:
            for layer_id in range(args.n_mtp_layers):
                self.mtp.append(DSparkBlock(args.n_layers + layer_id, args))
                self.mtp[-1].embed = self.embed
                self.mtp[-1].head = self.head
        self.hc_mult = args.hc_mult
        self.vision = None
        if args.vision_enabled:
            self.vision = ViT(args)
            self.aligner = Aligner(args)
            # learned embeddings for the image span delimiters
            self.image_start = nn.Parameter(torch.empty(args.dim))
            self.image_end = nn.Parameter(torch.empty(args.dim))
            self.image_newline = nn.Parameter(torch.empty(args.dim))

Direct evidence

Tokens are embedded and repeated into four streams; each layer, after an Engram step where it has one, reads and writes the streams; the last reading mix collapses them, then the final norm and the head.

transformer-forward · deepseek-ai/DeepSeek-V4.1-Flash / inference/model.py
Pinned revision 2cba9e42aa02 ↗ · lines 1241–1272

Read code excerpt
    @torch.inference_mode()
    def forward(
        self, input_ids: torch.Tensor, start_pos: int = 0, images=None, token_types: torch.Tensor | None = None
    ):
        """input_ids: [b, s], every entry a real token id -- generate.py only ever passes positions it
        has already filled, so the padding it uses internally never reaches here. token_types /
        images carry the VL inputs built by image_processor.prepare_vl_inputs; image spans must lie
        inside the first (start_pos 0) chunk."""
        image_mask = None if token_types is None else token_types >= 0  # TEXT is -1
        # image tokens take no part in an n-gram and get no engram contribution; text-only needs no mask
        engram_mask = None if image_mask is None else ~image_mask
        engram_hashes = self.engram_hash(input_ids, start_pos, engram_mask) if self.engram_hash is not None else None
        h = self.embed(input_ids)
        if images is not None:
            assert start_pos == 0, "image spans must be prefilled in a single chunk"
            self.merge_image_embeddings(images, h)
        # Expand to hc_mult copies for Hyper-Connections
        h = h.unsqueeze(2).repeat(1, 1, self.hc_mult, 1)
        main_hiddens = []
        pre_mix = make_identity_pre_mix(h, self.hc_mult)
        for i, layer in enumerate(self.layers):
            if layer.engram is not None:
                h = layer.engram(h, engram_hashes[:, :, layer.engram.layer_hash_index, :], engram_mask)
            # the MTP head reads the attention input of its target layers, not their output
            if i in self.target_layer_ids:
                main_hiddens.append(h.mean(dim=2))
            h, pre_mix = layer(h, start_pos, pre_mix, image_mask)
        h = layer.hc_pre(h, pre_mix)
        logits = self.head(self.norm(h))
        output_ids = sample(logits, self.temperature)
        main_hidden = torch.cat(main_hiddens, dim=-1) if main_hiddens else None
        return output_ids, logits, main_hidden