---
license: cc-by-4.0
configs:
- config_name: default
data_files:
- split: train
path: data/train-*
- split: test
path: data/test-*
dataset_info:
features:
- name: image
dtype: image
- name: ocr_text
dtype: string
- name: result
dtype: int64
splits:
- name: train
num_bytes: 60582512.0
num_examples: 10000
- name: test
num_bytes: 70989855.334
num_examples: 11766
download_size: 132297385
dataset_size: 131572367.334
task_categories:
- question-answering
tags:
- captcha
- math
- mathcaptcha
- math-captcha
- mvccaptcha
---

## Dataset Details
* **Dataset Name:** MathCaptcha10k
* **Curated by:** Atalay Denknalbant
* **License:** Creative Commons Attribution 4.0 International (CC BY 4.0)
* **Repository:** [https://www.kaggle.com/datasets/atalaydenknalbant/mathcaptcha10k](https://www.kaggle.com/datasets/atalaydenknalbant/mathcaptcha10k)
### Dataset Description
A corpus of 10 000 synthetic arithmetic‐captcha images rendered at 200×70 px. Each image contains exactly two base-10 numbers (1–2 digits), a single `+` or `–` operator, an `=` sign and a trailing question mark (e.g. `96-41=?`). Every example in the **train** split includes:
| image | ocr\_text | result |
| -------------------------- | --------- | ------ |
| `96-41=?` | "96-41=?" | 55 |
…where `ocr_text` is the exact characters in the image, and `result` is the integer answer.
The **test** split consists of 11 766 unlabeled captchas in `Unlabeled/` folder.
---
## Examples of the Captchas
**Easy example**

**Challenging example**

> Even state-of-the-art vision-language models often mis‐OCR the more distorted variants (see the “challenging” sample above).
---
## Uses
* **Direct uses**:
* Train and evaluate OCR/vision-language models on simple arithmetic recognition.
* Benchmark visual math-solving capabilities.
* **Out-of-scope uses**:
* Handwritten digit OCR.
* Complex mathematical notation beyond two-term arithmetic.
---
## Dataset Structure
* **Splits**
* `train` (10 000 labeled examples)
* `test` (11 766 `.png` files in `Unlabeled/`)
* **Features**
* `image` (PNG file)
* `ocr_text` (string, e.g. `"75-26=?"`)
* `result` (int, e.g. `49`)
---
## Dataset Creation
### Curation Rationale
Synthetic captchas provide a controlled environment for training and benchmarking. Even top tier vision language methods struggle with some distortions motivating manual QA to ensure label accuracy.
### Source Data
Programmatically generated using [CaptchaMvc.Mvc5](https://www.nuget.org/packages/CaptchaMvc.Mvc5)’s standard arithmetic template.
### Data Collection & Processing
1. Generate 10 000 PNG captchas via CaptchaMvc.Mvc5.
2. Run a VLM-based OCR pipeline, then manually verify and correct every label in a Streamlit QA app.
**Annotator:**
* Atalay Denknalbant
---
## Personal & Sensitive Information
None. Captchas contain no personal data.
---
## Bias, Risks & Limitations
* Purely synthetic; may not generalize to natural or handwritten text.
* Limited to two-term, 1–2 digit arithmetic.
---
## Recommendations
Combine with broader OCR datasets for real-world text recognition tasks.
---
## Citation
```bibtex
@misc{atalay_denknalbant_2025,
title = {MathCaptcha10k},
author = {Atalay Denknalbant},
year = {2025},
howpublished = {\url{https://www.kaggle.com/ds/7779792}},
publisher = {Kaggle},
DOI = {10.34740/KAGGLE/DS/7779792}
}
```
**APA**
> Denknalbant, A. (2025). *MathCaptcha10k* \[Data set]. Kaggle. [https://doi.org/10.34740/KAGGLE/DS/7779792](https://doi.org/10.34740/KAGGLE/DS/7779792)
## Dataset Card Authors
* Atalay Denknalbant
## Dataset Card Contact
* Atalay Denknalbant (questions & feedback)