SAM3 Alternatives

SAM 3 leads in open-vocabulary segmentation quality, but it's not the only option and not always the right one. This page compares SAM 3 against frontier VLLMs and popular non-VLLM models across benchmarks, latency, capabilities, and deployment fit.

Last updated: March 3, 2026

VLLM Benchmark Results

Counting and localisation on CountBench and PixMo-Count. MAE is lower-is-better; accuracy is higher-is-better. Color reflects rank within each row — green is best, red is weakest.

BenchmarkSAM 3Gemini 2.5 ProQwen2-VL-72BMolmo-72BDINO-X
CountBench MAE0.120.240.280.270.62
CountBench Accuracy (%)93.892.486.792.482.9
PixMo-Count MAE0.210.380.610.170.21
PixMo-Count Accuracy (%)86.278.263.788.885.0
Average Accuracy (%)90.085.375.290.684.0
Average MAE0.1650.3100.4450.2200.415

SAM 3 vs YOLO, FastSAM, and RF-DETR

The models teams most commonly evaluate for segmentation pipelines — compared across speed, accuracy, prompting approach, and deployment fit.

DimensionSAM 3SAM 2YOLO11-segFastSAMRF-DETR SegYOLOv12-N
Latency (ms / image)~30 ms~11 ms~1.8 ms~8 ms~4.4 ms~1.6 ms
Accuracy48.8 mask AP (LVIS, zero-shot)44.7 mask AP (LVIS)32.0 mask mAP (COCO)~37 mask mAP (COCO)43.1 mask mAP (COCO)40.6 box mAP (COCO)
Prompt typesPoint · box · text phrasePoint · boxClass labelPoint · box · textClass labelClass label
Open-vocabularyYesLimitedNoLimitedNoNo
Best fitZero-shot annotation & concept discoveryInteractive video segmentationEdge segmentationCPU-constrained promptingAccurate real-time detectionUltra-fast detection
Main tradeoffSlow on edge hardwareWeaker concept segmentationNo open-vocabulary supportLower quality ceilingHigher runtime complexityDetection only — no masks

Capability Matrix

Feature availability at a glance — useful for identifying where a model natively covers a workflow versus where custom engineering is needed.

CapabilitySAM 3SAM 2YOLO11-segFastSAMRF-DETRGemini 2.5
Zero-shot concept segmentation from noun phrasesYesNoNoPartialNoPartial
Per-instance segmentation masksYesYesYesYesYesNo
Unified image + video detector/trackerYesMemory-bank trackerNoNoNoNo
Interactive refinement (points/boxes)YesYesNoYesNoNo
Long instruction reasoning (no external agent)WeakWeakNoNoNoStrong

When to Use SAM 3

SAM 3 is the strongest model for open-vocabulary perception tasks, built for accuracy first. The right strategy depends on where in the pipeline the work happens:

  • Dataset construction & auto-labelling — Zero-shot mask quality is high enough to use directly as training labels without domain fine-tuning.
  • Interactive annotation — Point and box prompting with real-time mask preview makes SAM 3 the best tool for human-in-the-loop labelling workflows.
  • Production edge inference — Use SAM 3 to generate labelled data, then fine-tune YOLO or RF-DETR for sub-5ms edge serving.
  • Instruction-driven workflows — SAM 3 Agent decomposes complex queries into prompts and calls SAM 3 iteratively, beating prior work on ReasonSeg and OmniLabel out of the box.

Sources

  1. [1]DINO-X: A Unified Vision Model for Open-World Object Detection and Understanding (arXiv:2411.14347)Reference for DINO-X model.
  2. [2]Gemini 2.5 Technical Report — Google DeepMindReference for Gemini 2.5 Pro model. CountBench and PixMo-Count scores are from the SAM 3 paper.
  3. [3]Introducing SAM 3 — Meta AI Blog30 ms per-image latency on H200 with 100+ objects.
  4. [4]Molmo and PixMo: Open Weights and Open Data for State-of-the-Art VLMs — Deitke et al. (arXiv:2409.17146)Reference for Molmo-72B model. PixMo-Count benchmark originates from this work.
  5. [5]Qwen2-VL: Enhancing Vision-Language Model's Perception of the World at Any Resolution — Wang et al. (arXiv:2409.12191)Reference for Qwen2-VL-72B model.
  6. [6]RF-DETR Segmentation — Roboflow BlogRF-DETR Seg COCO mask mAP 50-95 and 4.4 ms latency figures.
  7. [7]SAM 3: Segment Anything with Concepts — Carion et al., Meta (arXiv:2511.16719, Nov 2025)LVIS zero-shot mask AP, CountBench / PixMo-Count benchmarks, H200 latency, SAM 3 Agent results on ReasonSeg and OmniLabel.
  8. [8]YOLO11 Documentation — UltralyticsYOLO11n-seg: 1.8 ms latency on T4 TensorRT10, 32.0 COCO mask mAP 50-95.
  9. [9]YOLOv12 GitHub Repository — sunsmarterjieYOLOv12-N: 1.64 ms latency, 40.6 COCO box mAP 50-95.