Key Capabilities
- Zero-shot classification - Predicts instantly through a single forward pass, no gradient descent required.
- Calibrated probabilities - Outputs reliable class probabilities for uncertainty-aware decision-making.
- Robust to noise and missing data - Handles categorical variables, uninformative columns, and outliers natively.
- Text-aware inputs - This API only feature automatically detects textual fields, extracts embeddings, and includes them in the forward pass for classification.
- Seamless multi-class support - Works out-of-the-box for binary and multi-class datasets.
Getting Started
ManyClassClassifier extension - available via Prior Labs Extensions.
It extends TabPFN to large multi-class problems using Error-Correcting Output Codes (ECOC), which:
- Encodes the multi-class task into multiple binary or small-class subtasks.
- Trains the base TabPFNClassifier on these subtasks.
- Decodes the results back into the original class space.
How can I improve classification speed, especially on large datasets?
How can I improve classification speed, especially on large datasets?
Each
predict() re-encodes the full training set in-context. Performance depends on:- Dataset size (e.g. TabPFN-2 is optimized for ≤10k samples)
- Fit mode (low_memory vs fit_with_cache)
- Device (CPU/MPS/GPU)
fit_with_cache retains preprocessing and significantly speeds up repeated predictions.How does TabPFN handle missing values?
How does TabPFN handle missing values?
TabPFNClassifier now supports native handling of missing values pd.NA. Older versions required manual preprocessing, but the current release integrates this automatically.We recommend upgrading to the latest version:Why is my classifier moving back to CPU after training or prediction?
Why is my classifier moving back to CPU after training or prediction?
After each inference, TabPFN’s inference engine automatically moves back to CPU to free GPU memory.
While this conserves resources, it slows down repeated predictions and can confuse users expecting persistent GPU behavior.