# Bat Output Styling Options: A Complete Guide to Customizing Syntax-Highlighted Output > Explore bat output styling options with the --style flag. Customize line numbers, Git markers, headers & grids or use presets like plain, default, and full for perfect syntax highlighting. - Repository: [David Peter/bat](https://github.com/sharkdp/bat) - Tags: deep-dive - Published: 2026-03-06 --- **Use the `--style` flag in bat to mix and match visual components like line numbers, Git change markers, headers, and grids, or choose presets like `plain`, `default`, and `full` to control exactly how file contents are displayed.** The `bat` command-line tool by sharkdp/bat enhances `cat` with syntax highlighting and Git integration. Central to its flexibility are the **bat output styling options**, which let you toggle individual visual decorations via the `--style` flag or the `BAT_STYLE` environment variable. These components are defined in [`src/style.rs`](https://github.com/sharkdp/bat/blob/main/src/style.rs) and applied through `App::style_components()` in [`src/bin/bat/app.rs`](https://github.com/sharkdp/bat/blob/main/src/bin/bat/app.rs). ## Understanding Bat Style Components Bat treats output styling as a composable system. Each style is a **component** that can be enabled, disabled, or combined with others. The parsing logic resides in `StyleComponentList::to_components` inside [`src/style.rs`](https://github.com/sharkdp/bat/blob/main/src/style.rs), which handles comma-separated lists and `+`/`-` modifiers to add or remove specific features from a base set. When bat renders a file, it checks the final component list to decide whether to draw line numbers, print file headers, show Git diff markers, or wrap the output in a decorative grid. ## Complete List of Bat Output Styling Options The following components are available in [`src/style.rs`](https://github.com/sharkdp/bat/blob/main/src/style.rs). You can combine them arbitrarily, though some combinations have special interactions (for example, `grid` overrides `rule`). ### Automatic and Preset Components - **`auto`** — Selects `default` when stdout is a TTY (interactive terminal) and `plain` when piped to another command or file. - **`default`** — The standard interactive view including `changes` (if compiled with Git support), `grid`, `header-filename`, `numbers`, and `snip`. - **`plain`** — Disables all decorations, outputting raw file content only. This is also accessible via the `--plain` (or `-p`) shorthand. - **`full`** — Enables every available component: `grid`, `header-filename`, `header-filesize`, `numbers`, `snip`, and `changes` (when the `git` feature is enabled). ### Individual Decoration Components - **`changes`** — Displays Git-aware change markers (`+` for added, `-` for removed, `!` for modified) in the gutter. Requires bat to be compiled with the `git` feature (enabled by default in official releases). - **`grid`** — Renders a full-width grid with vertical and horizontal lines, useful for visually separating files or tabular data. - **`rule`** — Draws a single horizontal rule (thin line). This is subsumed by `grid`; if both are requested, `rule` is ignored with a warning. - **`header`** — Shorthand for enabling both `header-filename` and `header-filesize`. - **`header-filename`** — Prints the file name as a header line before the content. - **`header-filesize`** — Prints the human-readable file size in the header. - **`numbers`** — Adds line numbers to every line. Accessible via the `-n` shorthand. - **`snip`** — Collapses long sections with an ellipsis (`…`) when terminal width forces wrapping, keeping the output compact. ## How to Use Bat Output Styling Options ### Basic Syntax and the `--style` Flag Pass a comma-separated list of components to the `--style` flag. Order does not matter, but later values can override earlier ones. ```bash # Enable only line numbers bat --style=numbers src/style.rs # Show filename header and line numbers bat --style=header-filename,numbers README.md ``` ### Combining and Overriding Components Use `+` and `-` prefixes to modify a base set. This is useful when you want to start from `default` or `full` and adjust specific features. ```bash # Start with default, remove the grid, add filesize header bat --style=default,-grid,+header-filesize # Full decorations except line numbers bat --style=full,-numbers ``` ### Using Environment Variables Set `BAT_STYLE` in your shell configuration to apply a default style to every invocation. This is parsed in [`src/bin/bat/config.rs`](https://github.com/sharkdp/bat/blob/main/src/bin/bat/config.rs). ```bash # Always use plain mode in scripts export BAT_STYLE=plain # Prefer a compact view with numbers but no grid export BAT_STYLE=numbers,header-filename ``` ## Practical Examples of Bat Styling Here are common use cases demonstrating how to leverage bat output styling options for different workflows. **Viewing a file with Git changes highlighted:** ```bash bat --style=changes,numbers src/main.rs ``` **Creating a clean pipe-friendly output (no colors, no decorations):** ```bash bat --style=plain app.py | grep "def " ``` **Displaying a CSV with grid lines for better readability:** ```bash bat --style=grid data.csv ``` **Comparing two files with full metadata and line numbers:** ```bash bat --style=full file1.txt file2.txt ``` **Removing line numbers from the default view for cleaner screenshots:** ```bash bat --style=default,-numbers config.yml ``` ## Implementation Details The styling system is implemented across several core files in the sharkdp/bat repository. In [`src/style.rs`](https://github.com/sharkdp/bat/blob/main/src/style.rs), the `StyleComponent` enum defines all available components, while `StyleComponentList` handles parsing and merging logic via `to_components()`. This supports the `+` and `-` prefix syntax for incremental modifications. The application layer in [`src/bin/bat/app.rs`](https://github.com/sharkdp/bat/blob/main/src/bin/bat/app.rs) contains `App::style_components()`, which resolves the final component set by combining CLI arguments, environment variables (`BAT_STYLE`), and default values. This method determines whether stdout is a TTY to handle the `auto` component correctly. Command-line parsing is defined in [`src/bin/bat/clap_app.rs`](https://github.com/sharkdp/bat/blob/main/src/bin/bat/clap_app.rs), which documents the `--style`, `--plain`, and `--number` flags. Environment variable integration is managed in [`src/bin/bat/config.rs`](https://github.com/sharkdp/bat/blob/main/src/bin/bat/config.rs), mapping `BAT_STYLE` to the internal configuration structure. ## Summary - **Bat output styling options** are controlled via the `--style` flag or `BAT_STYLE` environment variable, accepting comma-separated components. - **Components** include `numbers`, `header`, `grid`, `changes` (Git markers), `snip`, and presets like `plain`, `default`, `full`, and `auto`. - **Syntax modifiers** allow incremental adjustments using `+` and `-` prefixes (e.g., `--style=default,-grid`). - **Source implementation** resides in [`src/style.rs`](https://github.com/sharkdp/bat/blob/main/src/style.rs) (definitions), [`src/bin/bat/app.rs`](https://github.com/sharkdp/bat/blob/main/src/bin/bat/app.rs) (application logic), and [`src/bin/bat/config.rs`](https://github.com/sharkdp/bat/blob/main/src/bin/bat/config.rs) (environment variables). ## Frequently Asked Questions ### What is the difference between `bat --style=plain` and `bat --plain`? There is no functional difference; `--plain` is a shorthand alias for `--style=plain`. Both disable all decorations, outputting raw file content without line numbers, headers, grids, or syntax highlighting backgrounds. The `--plain` flag is defined in [`src/bin/bat/clap_app.rs`](https://github.com/sharkdp/bat/blob/main/src/bin/bat/clap_app.rs) as a convenience shortcut. ### How do I show Git change markers in bat output? Enable the `changes` component with `bat --style=changes` or include it in a combination like `bat --style=changes,numbers`. This displays `+`, `-`, or `!` markers in the gutter indicating added, removed, or modified lines according to Git. Note that this requires bat to be compiled with the `git` feature, which is enabled by default in official releases but may be disabled in minimal builds. ### Can I set a default style for all bat commands? Yes, set the `BAT_STYLE` environment variable in your shell configuration file (e.g., `.bashrc`, `.zshrc`, or `config.fish`). For example, `export BAT_STYLE=numbers,header-filename` applies that style to every bat invocation. This is parsed in [`src/bin/bat/config.rs`](https://github.com/sharkdp/bat/blob/main/src/bin/bat/config.rs) and can be overridden per-command with the `--style` flag. ### Why does `bat --style=rule,grid` only show the grid? When both `rule` and `grid` are requested, `grid` takes precedence and `rule` is ignored with a warning. This is because `grid` renders a full box drawing including horizontal lines, making the single horizontal `rule` redundant. The logic handling this conflict is implemented in the style component resolution code within [`src/style.rs`](https://github.com/sharkdp/bat/blob/main/src/style.rs).