# How to Use holehe from the Command Line: Complete OSINT Email Scanning Guide > Master holehe from the command line for OSINT email scanning. Discover email registrations across 120+ services with this powerful Python tool. Get started now. - Repository: [Palenath/holehe](https://github.com/megadose/holehe) - Tags: how-to-guide - Published: 2026-08-21 --- **holehe is an asynchronous Python OSINT tool that checks if an email address is registered across 120+ online services via a simple command-line interface with optional CSV export and filtering.** The `megadose/holehe` repository provides a robust command-line utility for digital investigations and reconnaissance. When you use holehe from the command line, you trigger an asynchronous workflow that queries "forgot password" endpoints to verify account existence without sending notifications to the target address. ## Basic Syntax and Prerequisites Ensure holehe is installed via pip before executing commands. The CLI entry point is defined in [`holehe/core.py`](https://github.com/megadose/holehe/blob/main/holehe/core.py), where `holehe.main()` delegates control to the async `maincore()` function. The positional argument structure follows this pattern: ```bash holehe [email@address.com] [options] ``` ## Core Command Line Options The `ArgumentParser` in [`holehe/core.py`](https://github.com/megadose/holehe/blob/main/holehe/core.py) (lines 80-96) requires a target email address and supports several optional flags that control result filtering and output formatting. ### Running a Basic Email Scan To check a single email against all supported platforms, provide the address as the sole positional argument: ```bash holehe test@example.com ``` This command initiates the full scanning pipeline: `import_submodules()` discovers all modules under `holehe/modules`, `get_functions()` filters them into callables (lines 37-64), and each checker executes concurrently via `launch_module()`. ### Filtering for Active Accounts Only To display only services where the email is actually registered, append the `--only-used` flag: ```bash holehe test@example.com --only-used ``` This option filters the final result set after all asynchronous tasks complete, suppressing negative matches and showing only confirmed registrations. ### Controlling Output Format For log files or CI/CD environments where ANSI colors cause formatting issues, disable colored output with `--no-color`: ```bash holehe test@example.com --no-color ``` To export results for spreadsheet analysis or reporting, use the `--csv` flag: ```bash holehe test@example.com --csv ``` ## Understanding the Asynchronous Architecture When you invoke holehe from the terminal, `maincore()` orchestrates a five-stage asynchronous workflow defined in [`holehe/core.py`](https://github.com/megadose/holehe/blob/main/holehe/core.py): 1. **Argument validation** – The `ArgumentParser` verifies the email format and parses optional flags. 2. **Module discovery** – `import_submodules()` dynamically loads all sub-modules under `holehe/modules`, while `get_functions()` extracts the service-specific check functions. 3. **HTTP client setup** – An `httpx.AsyncClient` is instantiated for efficient, connection-pooled HTTP/2 requests. 4. **Concurrent execution** – Each service checker runs inside `launch_module()` within a Trio nursery (lines 166-173), enabling parallel execution across 120+ platforms while managing rate limits. 5. **Result processing** – After the nursery closes, results sort alphabetically and print with status symbols (✅, ❌, or ⚠️) before optional CSV export. ## Advanced Usage and Flag Combinations You can chain multiple options to customize both the scan scope and output destination: ```bash holehe test@example.com --only-used --no-color --csv ``` This combination exports only confirmed accounts to CSV format without color codes, ideal for automated logging or integration with other reconnaissance tools. ## Summary - **Entry point**: The `holehe` command calls `maincore()` in [`holehe/core.py`](https://github.com/megadose/holehe/blob/main/holehe/core.py) (lines 32-34) through the Trio async framework. - **Target specification**: Provide exactly one email address as the required positional argument. - **Filtering**: Use `--only-used` to show only services where the email is registered. - **Output control**: `--no-color` disables terminal colors, and `--csv` enables spreadsheet export. - **Concurrency**: The tool leverages `httpx.AsyncClient` and Trio nurseries to parallelize checks across all available modules without manual configuration. ## Frequently Asked Questions ### How does holehe check so many services simultaneously? According to the megadose/holehe source code in [`holehe/core.py`](https://github.com/megadose/holehe/blob/main/holehe/core.py), the tool creates an `httpx.AsyncClient` and launches each service module inside a Trio nursery via `launch_module()` (lines 166-173). This architecture enables concurrent HTTP requests while the async event loop manages connection pooling and rate limiting across all 120+ platforms. ### Why does holehe scan every available service instead of specific ones? The `import_submodules()` function dynamically imports all Python files under `holehe/modules` and `get_functions()` extracts their check functions (lines 37-64). This design ensures comprehensive OSINT coverage by default, running every available "forgot password" check without requiring users to manually specify target services. ### Can I run holehe in automated scripts or pipelines? Yes. The `--no-color` flag removes ANSI escape sequences for plain-text logging, and `--csv` generates machine-readable output suitable for data processing. These options, implemented in the `ArgumentParser` (lines 80-96), make holehe compatible with cron jobs, CI/CD pipelines, and automated reconnaissance workflows. ### Does the CLI support checking multiple emails in one command? The current implementation in `maincore()` accepts only a single positional email argument. For batch processing multiple addresses, you must invoke the command sequentially within a shell loop or script, as the underlying architecture processes one target email per execution context.