--- name: gradio description: Build Gradio web UIs and demos in Python. Use when creating or editing Gradio apps, components, event listeners, layouts, or chatbots. --- # Gradio Gradio is a Python library for building interactive web UIs and ML demos. This skill covers the core API, patterns, and examples. ## Guides Detailed guides on specific topics (read these when relevant): - [Quickstart](https://www.gradio.app/guides/quickstart) - [The Interface Class](https://www.gradio.app/guides/the-interface-class) - [Blocks and Event Listeners](https://www.gradio.app/guides/blocks-and-event-listeners) - [Controlling Layout](https://www.gradio.app/guides/controlling-layout) - [More Blocks Features](https://www.gradio.app/guides/more-blocks-features) - [Custom CSS and JS](https://www.gradio.app/guides/custom-CSS-and-JS) - [Streaming Outputs](https://www.gradio.app/guides/streaming-outputs) - [Streaming Inputs](https://www.gradio.app/guides/streaming-inputs) - [Sharing Your App](https://www.gradio.app/guides/sharing-your-app) - [Custom HTML Components](https://www.gradio.app/guides/custom-HTML-components) - [Getting Started with the Python Client](https://www.gradio.app/guides/getting-started-with-the-python-client) - [Getting Started with the JS Client](https://www.gradio.app/guides/getting-started-with-the-js-client) ## Core Patterns **Interface** (high-level): wraps a function with input/output components. ```python import gradio as gr def greet(name): return f"Hello {name}!" gr.Interface(fn=greet, inputs="text", outputs="text").launch() ``` **Blocks** (low-level): flexible layout with explicit event wiring. ```python import gradio as gr with gr.Blocks() as demo: name = gr.Textbox(label="Name") output = gr.Textbox(label="Greeting") btn = gr.Button("Greet") btn.click(fn=lambda n: f"Hello {n}!", inputs=name, outputs=output) demo.launch() ``` **ChatInterface**: high-level wrapper for chatbot UIs. ```python import gradio as gr def respond(message, history): return f"You said: {message}" gr.ChatInterface(fn=respond).launch() ``` ## Key Component Signatures ### `Textbox(value: str | I18nData | Callable | None = None, type: Literal['text', 'password', 'email'] = "text", lines: int = 1, max_lines: int | None = None, placeholder: str | I18nData | None = None, label: str | I18nData | None = None, info: str | I18nData | None = None, every: Timer | float | None = None, inputs: Component | Sequence[Component] | set[Component] | None = None, show_label: bool | None = None, container: bool = True, scale: int | None = None, min_width: int = 160, interactive: bool | None = None, visible: bool | Literal['hidden'] = True, elem_id: str | None = None, autofocus: bool = False, autoscroll: bool = True, elem_classes: list[str] | str | None = None, render: bool = True, key: int | str | tuple[int | str, ...] | None = None, preserved_by_key: list[str] | str | None = "value", text_align: Literal['left', 'right'] | None = None, rtl: bool = False, buttons: list[Literal['copy'] | Button] | None = None, max_length: int | None = None, submit_btn: str | bool | None = False, stop_btn: str | bool | None = False, html_attributes: InputHTMLAttributes | None = None)` Creates a textarea for user to enter string input or display string output.. ### `Number(value: float | Callable | None = None, label: str | I18nData | None = None, placeholder: str | I18nData | None = None, info: str | I18nData | None = None, every: Timer | float | None = None, inputs: Component | Sequence[Component] | set[Component] | None = None, show_label: bool | None = None, container: bool = True, scale: int | None = None, min_width: int = 160, interactive: bool | None = None, visible: bool | Literal['hidden'] = True, elem_id: str | None = None, elem_classes: list[str] | str | None = None, render: bool = True, key: int | str | tuple[int | str, ...] | None = None, preserved_by_key: list[str] | str | None = "value", buttons: list[Button] | None = None, precision: int | None = None, minimum: float | None = None, maximum: float | None = None, step: float = 1)` Creates a numeric field for user to enter numbers as input or display numeric output.. ### `Slider(minimum: float = 0, maximum: float = 100, value: float | Callable | None = None, step: float | None = None, precision: int | None = None, label: str | I18nData | None = None, info: str | I18nData | None = None, every: Timer | float | None = None, inputs: Component | Sequence[Component] | set[Component] | None = None, show_label: bool | None = None, container: bool = True, scale: int | None = None, min_width: int = 160, interactive: bool | None = None, visible: bool | Literal['hidden'] = True, elem_id: str | None = None, elem_classes: list[str] | str | None = None, render: bool = True, key: int | str | tuple[int | str, ...] | None = None, preserved_by_key: list[str] | str | None = "value", randomize: bool = False, buttons: list[Literal['reset']] | None = None)` Creates a slider that ranges from {minimum} to {maximum} with a step size of {step}.. ### `Checkbox(value: bool | Callable = False, label: str | I18nData | None = None, info: str | I18nData | None = None, every: Timer | float | None = None, inputs: Component | Sequence[Component] | set[Component] | None = None, show_label: bool | None = None, container: bool = True, scale: int | None = None, min_width: int = 160, interactive: bool | None = None, visible: bool | Literal['hidden'] = True, elem_id: str | None = None, elem_classes: list[str] | str | None = None, render: bool = True, key: int | str | tuple[int | str, ...] | None = None, preserved_by_key: list[str] | str | None = "value", buttons: list[Button] | None = None)` Creates a checkbox that can be set to `True` or `False`. ### `Dropdown(choices: Sequence[str | int | float | tuple[str, str | int | float]] | None = None, value: str | int | float | Sequence[str | int | float] | Callable | DefaultValue | None = DefaultValue(), type: Literal['value', 'index'] = "value", multiselect: bool | None = None, allow_custom_value: bool = False, max_choices: int | None = None, filterable: bool = True, label: str | I18nData | None = None, info: str | I18nData | None = None, every: Timer | float | None = None, inputs: Component | Sequence[Component] | set[Component] | None = None, show_label: bool | None = None, container: bool = True, scale: int | None = None, min_width: int = 160, interactive: bool | None = None, visible: bool | Literal['hidden'] = True, elem_id: str | None = None, elem_classes: list[str] | str | None = None, render: bool = True, key: int | str | tuple[int | str, ...] | None = None, preserved_by_key: list[str] | str | None = "value", buttons: list[Button] | None = None)` Creates a dropdown of choices from which a single entry or multiple entries can be selected (as an input component) or displayed (as an output component).. ### `Radio(choices: Sequence[str | int | float | tuple[str, str | int | float]] | None = None, value: str | int | float | Callable | None = None, type: Literal['value', 'index'] = "value", label: str | I18nData | None = None, info: str | I18nData | None = None, every: Timer | float | None = None, inputs: Component | Sequence[Component] | set[Component] | None = None, show_label: bool | None = None, container: bool = True, scale: int | None = None, min_width: int = 160, interactive: bool | None = None, visible: bool | Literal['hidden'] = True, elem_id: str | None = None, elem_classes: list[str] | str | None = None, render: bool = True, key: int | str | tuple[int | str, ...] | None = None, preserved_by_key: list[str] | str | None = "value", rtl: bool = False, buttons: list[Button] | None = None)` Creates a set of (string or numeric type) radio buttons of which only one can be selected.. ### `Image(value: str | PIL.Image.Image | np.ndarray | Callable | None = None, format: str = "webp", height: int | str | None = None, width: int | str | None = None, image_mode: Literal['1', 'L', 'P', 'RGB', 'RGBA', 'CMYK', 'YCbCr', 'LAB', 'HSV', 'I', 'F'] | None = "RGB", sources: list[Literal['upload', 'webcam', 'clipboard']] | Literal['upload', 'webcam', 'clipboard'] | None = None, type: Literal['numpy', 'pil', 'filepath'] = "numpy", label: str | I18nData | None = None, every: Timer | float | None = None, inputs: Component | Sequence[Component] | set[Component] | None = None, show_label: bool | None = None, buttons: list[Literal['download', 'share', 'fullscreen'] | Button] | None = None, container: bool = True, scale: int | None = None, min_width: int = 160, interactive: bool | None = None, visible: bool | Literal['hidden'] = True, streaming: bool = False, elem_id: str | None = None, elem_classes: list[str] | str | None = None, render: bool = True, key: int | str | tuple[int | str, ...] | None = None, preserved_by_key: list[str] | str | None = "value", webcam_options: WebcamOptions | None = None, placeholder: str | None = None, watermark: WatermarkOptions | None = None)` Creates an image component that can be used to upload images (as an input) or display images (as an output).. ### `Audio(value: str | Path | tuple[int, np.ndarray] | Callable | None = None, sources: list[Literal['upload', 'microphone']] | Literal['upload', 'microphone'] | None = None, type: Literal['numpy', 'filepath'] = "numpy", label: str | I18nData | None = None, every: Timer | float | None = None, inputs: Component | Sequence[Component] | set[Component] | None = None, show_label: bool | None = None, container: bool = True, scale: int | None = None, min_width: int = 160, interactive: bool | None = None, visible: bool | Literal['hidden'] = True, streaming: bool = False, elem_id: str | None = None, elem_classes: list[str] | str | None = None, render: bool = True, key: int | str | tuple[int | str, ...] | None = None, preserved_by_key: list[str] | str | None = "value", format: Literal['wav', 'mp3'] | None = None, autoplay: bool = False, editable: bool = True, buttons: list[Literal['download', 'share'] | Button] | None = None, waveform_options: WaveformOptions | dict | None = None, loop: bool = False, recording: bool = False, subtitles: str | Path | list[dict[str, Any]] | None = None, playback_position: float = 0)` Creates an audio component that can be used to upload/record audio (as an input) or display audio (as an output).. ### `Video(value: str | Path | Callable | None = None, format: str | None = None, sources: list[Literal['upload', 'webcam']] | Literal['upload', 'webcam'] | None = None, height: int | str | None = None, width: int | str | None = None, label: str | I18nData | None = None, every: Timer | float | None = None, inputs: Component | Sequence[Component] | set[Component] | None = None, show_label: bool | None = None, container: bool = True, scale: int | None = None, min_width: int = 160, interactive: bool | None = None, visible: bool | Literal['hidden'] = True, elem_id: str | None = None, elem_classes: list[str] | str | None = None, render: bool = True, key: int | str | tuple[int | str, ...] | None = None, preserved_by_key: list[str] | str | None = "value", webcam_options: WebcamOptions | None = None, include_audio: bool | None = None, autoplay: bool = False, buttons: list[Literal['download', 'share'] | Button] | None = None, loop: bool = False, streaming: bool = False, watermark: WatermarkOptions | None = None, subtitles: str | Path | list[dict[str, Any]] | None = None, playback_position: float = 0)` Creates a video component that can be used to upload/record videos (as an input) or display videos (as an output). ### `File(value: str | list[str] | Callable | None = None, file_count: Literal['single', 'multiple', 'directory'] = "single", file_types: list[str] | None = None, type: Literal['filepath', 'binary'] = "filepath", label: str | I18nData | None = None, every: Timer | float | None = None, inputs: Component | Sequence[Component] | set[Component] | None = None, show_label: bool | None = None, container: bool = True, scale: int | None = None, min_width: int = 160, height: int | str | float | None = None, interactive: bool | None = None, visible: bool | Literal['hidden'] = True, elem_id: str | None = None, elem_classes: list[str] | str | None = None, render: bool = True, key: int | str | tuple[int | str, ...] | None = None, preserved_by_key: list[str] | str | None = "value", allow_reordering: bool = False, buttons: list[Button] | None = None)` Creates a file component that allows uploading one or more generic files (when used as an input) or displaying generic files or URLs for download (as output). ### `Chatbot(value: list[MessageDict | Message] | Callable | None = None, label: str | I18nData | None = None, every: Timer | float | None = None, inputs: Component | Sequence[Component] | set[Component] | None = None, show_label: bool | None = None, container: bool = True, scale: int | None = None, min_width: int = 160, visible: bool | Literal['hidden'] = True, elem_id: str | None = None, elem_classes: list[str] | str | None = None, autoscroll: bool = True, render: bool = True, key: int | str | tuple[int | str, ...] | None = None, preserved_by_key: list[str] | str | None = "value", height: int | str | None = 400, resizable: bool = False, max_height: int | str | None = None, min_height: int | str | None = None, editable: Literal['user', 'all'] | None = None, latex_delimiters: list[dict[str, str | bool]] | None = None, rtl: bool = False, buttons: list[Literal['share', 'copy', 'copy_all'] | Button] | None = None, watermark: str | None = None, avatar_images: tuple[str | Path | None, str | Path | None] | None = None, sanitize_html: bool = True, render_markdown: bool = True, feedback_options: list[str] | tuple[str, ...] | None = ('Like', 'Dislike'), feedback_value: Sequence[str | None] | None = None, line_breaks: bool = True, layout: Literal['panel', 'bubble'] | None = None, placeholder: str | None = None, examples: list[ExampleMessage] | None = None, allow_file_downloads: = True, group_consecutive_messages: bool = True, allow_tags: list[str] | bool = True, reasoning_tags: list[tuple[str, str]] | None = None, like_user_message: bool = False)` Creates a chatbot that displays user-submitted messages and responses. ### `Button(value: str | I18nData | Callable = "Run", every: Timer | float | None = None, inputs: Component | Sequence[Component] | set[Component] | None = None, variant: Literal['primary', 'secondary', 'stop', 'huggingface'] = "secondary", size: Literal['sm', 'md', 'lg'] = "lg", icon: str | Path | None = None, link: str | None = None, link_target: Literal['_self', '_blank', '_parent', '_top'] = "_self", visible: bool | Literal['hidden'] = True, interactive: bool = True, elem_id: str | None = None, elem_classes: list[str] | str | None = None, render: bool = True, key: int | str | tuple[int | str, ...] | None = None, preserved_by_key: list[str] | str | None = "value", scale: int | None = None, min_width: int | None = None)` Creates a button that can be assigned arbitrary .click() events. ### `Markdown(value: str | I18nData | Callable | None = None, label: str | I18nData | None = None, every: Timer | float | None = None, inputs: Component | Sequence[Component] | set[Component] | None = None, show_label: bool | None = None, rtl: bool = False, latex_delimiters: list[dict[str, str | bool]] | None = None, visible: bool | Literal['hidden'] = True, elem_id: str | None = None, elem_classes: list[str] | str | None = None, render: bool = True, key: int | str | tuple[int | str, ...] | None = None, preserved_by_key: list[str] | str | None = "value", sanitize_html: bool = True, line_breaks: bool = False, header_links: bool = False, height: int | str | None = None, max_height: int | str | None = None, min_height: int | str | None = None, buttons: list[Literal['copy']] | None = None, container: bool = False, padding: bool = False)` Used to render arbitrary Markdown output. ### `HTML(value: Any | Callable | None = None, label: str | I18nData | None = None, html_template: str = "${value}", css_template: str = "", js_on_load: str | None = "element.addEventListener('click', function() { trigger('click') });", apply_default_css: bool = True, every: Timer | float | None = None, inputs: Component | Sequence[Component] | set[Component] | None = None, show_label: bool = False, visible: bool | Literal['hidden'] = True, elem_id: str | None = None, elem_classes: list[str] | str | None = None, render: bool = True, key: int | str | tuple[int | str, ...] | None = None, preserved_by_key: list[str] | str | None = "value", min_height: int | None = None, max_height: int | None = None, container: bool = False, padding: bool = False, autoscroll: bool = False, buttons: list[Button] | None = None, props: Any)` Creates a component with arbitrary HTML. ## Custom HTML Components If a task requires significant customization of an existing component or a component that doesn't exist in Gradio, you can create one with `gr.HTML`. It supports `html_template` (with `${}` JS expressions and `{{}}` Handlebars syntax), `css_template` for scoped styles, and `js_on_load` for interactivity — where `props.value` updates the component value and `trigger('event_name')` fires Gradio events. For reuse, subclass `gr.HTML` and define `api_info()` for API/MCP support. See the [full guide](https://www.gradio.app/guides/custom-HTML-components). Here's an example that shows how to create and use these kinds of components: ```python import gradio as gr class StarRating(gr.HTML): def __init__(self, label, value=0, **kwargs): html_template = """

${label} rating:

${Array.from({length: 5}, (_, i) => ``).join('')} """ css_template = """ img { height: 50px; display: inline-block; cursor: pointer; } .faded { filter: grayscale(100%); opacity: 0.3; } """ js_on_load = """ const imgs = element.querySelectorAll('img'); imgs.forEach((img, index) => { img.addEventListener('click', () => { props.value = index + 1; }); }); """ super().__init__(value=value, label=label, html_template=html_template, css_template=css_template, js_on_load=js_on_load, **kwargs) def api_info(self): return {"type": "integer", "minimum": 0, "maximum": 5} with gr.Blocks() as demo: gr.Markdown("# Restaurant Review") food_rating = StarRating(label="Food", value=3) service_rating = StarRating(label="Service", value=3) ambience_rating = StarRating(label="Ambience", value=3) average_btn = gr.Button("Calculate Average Rating") rating_output = StarRating(label="Average", value=3) def calculate_average(food, service, ambience): return round((food + service + ambience) / 3) average_btn.click( fn=calculate_average, inputs=[food_rating, service_rating, ambience_rating], outputs=rating_output ) demo.launch() ``` ## Event Listeners All event listeners share the same signature: ```python component.event_name( fn: Callable | None | Literal["decorator"] = "decorator", inputs: Component | Sequence[Component] | set[Component] | None = None, outputs: Component | Sequence[Component] | set[Component] | None = None, api_name: str | None = None, api_description: str | None | Literal[False] = None, scroll_to_output: bool = False, show_progress: Literal["full", "minimal", "hidden"] = "full", show_progress_on: Component | Sequence[Component] | None = None, queue: bool = True, batch: bool = False, max_batch_size: int = 4, preprocess: bool = True, postprocess: bool = True, cancels: dict[str, Any] | list[dict[str, Any]] | None = None, trigger_mode: Literal["once", "multiple", "always_last"] | None = None, js: str | Literal[True] | None = None, concurrency_limit: int | None | Literal["default"] = "default", concurrency_id: str | None = None, api_visibility: Literal["public", "private", "undocumented"] = "public", time_limit: int | None = None, stream_every: float = 0.5, key: int | str | tuple[int | str, ...] | None = None, validator: Callable | None = None, ) -> Dependency ``` Supported events per component: - **AnnotatedImage**: select - **Audio**: stream, change, clear, play, pause, stop, pause, start_recording, pause_recording, stop_recording, upload, input - **BarPlot**: select, double_click - **BrowserState**: change - **Button**: click - **Chatbot**: change, select, like, retry, undo, example_select, option_select, clear, copy, edit - **Checkbox**: change, input, select - **CheckboxGroup**: change, input, select - **ClearButton**: click - **Code**: change, input, focus, blur - **ColorPicker**: change, input, submit, focus, blur - **Dataframe**: change, input, select, edit - **Dataset**: click, select - **DateTime**: change, submit - **DeepLinkButton**: click - **Dialogue**: change, input, submit - **DownloadButton**: click - **Dropdown**: change, input, select, focus, blur, key_up - **DuplicateButton**: click - **File**: change, select, clear, upload, delete, download - **FileExplorer**: change, input, select - **Gallery**: select, upload, change, delete, preview_close, preview_open - **HTML**: change, input, click, double_click, submit, stop, edit, clear, play, pause, end, start_recording, pause_recording, stop_recording, focus, blur, upload, release, select, stream, like, example_select, option_select, load, key_up, apply, delete, tick, undo, retry, expand, collapse, download, copy - **HighlightedText**: change, select - **Image**: clear, change, stream, select, upload, input - **ImageEditor**: clear, change, input, select, upload, apply - **ImageSlider**: clear, change, stream, select, upload, input - **JSON**: change - **Label**: change, select - **LinePlot**: select, double_click - **LoginButton**: click - **Markdown**: change, copy - **Model3D**: change, upload, edit, clear - **MultimodalTextbox**: change, input, select, submit, focus, blur, stop - **Navbar**: change - **Number**: change, input, submit, focus, blur - **ParamViewer**: change, upload - **Plot**: change - **Radio**: select, change, input - **ScatterPlot**: select, double_click - **SimpleImage**: clear, change, upload - **Slider**: change, input, release - **State**: change - **Textbox**: change, input, select, submit, focus, blur, stop, copy - **Timer**: tick - **UploadButton**: click, upload - **Video**: change, clear, start_recording, stop_recording, stop, play, pause, end, upload, input ## Additional Reference - [End-to-End Examples](examples.md) — complete working apps