--- title: "Deskewing PDF pages | Nutrient Python SDK" canonical_url: "https://www.nutrient.io/guides/python/editor/deskew-pdf-page/" md_url: "https://www.nutrient.io/guides/python/editor/deskew-pdf-page.md" last_updated: "2026-08-10T00:00:00.000Z" description: "How to deskew scanned PDF pages using Nutrient Python SDK." --- # Deskewing PDF pages Pages that come off a scanner or a phone camera are rarely square to the page. A few degrees of rotation is enough to hurt OCR accuracy, throw off barcode and table detection, and make an otherwise clean archive look sloppy. Deskewing straightens the page before any of that downstream work runs. Deskewing at the page level keeps the operation narrow. You correct the pages you know came from a scanner and leave the rest of the document untouched, which matters in mixed documents where born-digital pages are already square. This sample shows how to straighten a single page of a document using Nutrient Python SDK and save the result. The input can be any document format the SDK supports. If the input isn't already a PDF, the SDK converts it to PDF automatically when you create the editor. [Download sample](https://www.nutrient.io/downloads/samples/python/deskew-pdf-page.zip) ## How Nutrient helps Nutrient Python SDK detects and corrects skew behind a single method call. The SDK: - Implicitly converts non-PDF inputs (images, multi-page TIFFs, Office documents) to PDF when the editor is created - Rasterizes the target page and measures its dominant text baseline angle - Rotates the page content by the detected angle to bring it back to square - Applies the correction to the page content stream, so text and vector art stay vector — the page isn't flattened to an image - Leaves the page alone when no skew is detected Other pages in the document aren't touched. ## Preparing the project Import the classes used in the sample: ```python from nutrient_sdk import Document from nutrient_sdk import PdfEditor from nutrient_sdk import NutrientException ``` ## Opening the document Open the source document and attach a PDF editor to it: ```python def main(): try: with Document.open("input_skewed_scan.pdf") as document: editor = PdfEditor.edit(document) ``` `PdfEditor.edit(document)` attaches an editor to the open document. If the input isn't already a PDF, the SDK converts it to PDF at this step. The [context manager](https://docs.python.org/3/reference/datamodel.html#context-managers) closes the document when the block exits, even if deskewing raises. ## Tuning detection Three document settings control the detector, and they must be set before you deskew. `skew_tolerance` is the search window in degrees — skew larger than this isn't corrected. Narrow it when you know your scans are only slightly off and you want to avoid over-correcting a page whose layout merely looks slanted. `optimistic_skew_detection` relaxes the confidence checks that suppress a borderline result. Enable it when you already know a batch is skewed and the conservative pass is reporting nothing. Leave it off for mixed input, where it raises the chance of rotating a page that was actually straight. `skew_binarization_method` chooses how the page is reduced to black and white before the skew is measured. Set it to `"sauvola"` for faint, grayish, or unevenly lit scans, where a global threshold loses too much text for the detector to lock onto. `"default"` and `"otsu"` both use Modified Otsu. ```python document.settings.deskew_settings.skew_tolerance = 10.0 document.settings.deskew_settings.optimistic_skew_detection = False document.settings.deskew_settings.skew_binarization_method = "default" ``` All three have sensible defaults (a 15-degree window, conservative detection, Modified Otsu), so you can skip this step entirely and call `auto_deskew()` directly. These settings are shared with the recognition pipelines, so the same values apply if you later run OCR or data extraction over the document. The other properties on `DeskewSettings` cover model-based cardinal orientation correction, which runs only in those pipelines and doesn't affect a page-level deskew. ## Straightening a single page Get the target page from the editor and deskew it: ```python pages = editor.get_page_collection() page = pages.get_first() applied_angle = page.auto_deskew() if applied_angle!= 0: print(f"Corrected a skew of {applied_angle:.2f} degrees.") else: print("No skew detected, page left unchanged.") ``` `editor.get_page_collection().get_first()` returns the first page of the document, and `auto_deskew()` measures that page's skew and rotates its content to correct it. A page the detector reads as already square is left unchanged, so the call is safe to run over pages you aren't sure about. The return value is the rotation that was applied, in degrees, and is `0` when nothing was corrected. Use it to log what happened or to flag pages that came in badly skewed. To target a different page, use the page collection accessor (for example `pages.get(2)` for the third page) and call `auto_deskew()` on that page instead. ## Saving the result Save the modified document to a new file and close the editor: ```python editor.save_as("output.pdf") editor.close() except NutrientException as e: print(f"Error: {e}") if __name__ == "__main__": main() ``` The `except` clause surfaces any licensing or I/O issue raised by the SDK. Deskewing requires an unencrypted document — an encrypted source raises an error rather than silently skipping the page. ## Conclusion The workflow for deskewing a single PDF page is: 1. Open the source document. 2. Create a `PdfEditor` for the document. 3. Optionally tune `skew_tolerance` and `optimistic_skew_detection` on the document settings. 4. Get the target page from `editor.get_page_collection()`. 5. Call `auto_deskew()` on that page. 6. Save the result and close the editor. Only the targeted page is straightened. The rest of the document is left as it was. For related workflows, refer to the [Python SDK guides](https://www.nutrient.io/guides/python.md). --- ## Related pages - [Nutrient Python SDK editor guides](/guides/python/editor.md) - [Adding annotations to a PDF document](/guides/python/editor/add-annotations-to-pdf.md) - [Adding a custom page to a PDF document](/guides/python/editor/add-custom-page-to-pdf.md) - [Adding interactive form fields to a PDF document](/guides/python/editor/add-form-fields-to-pdf.md) - [Adding free text annotations to a PDF document](/guides/python/editor/add-freetext-annotations-to-pdf.md) - [Adding invisible digital signatures to a PDF document](/guides/python/editor/add-invisible-signature-to-pdf.md) - [Adding link annotations to a PDF document](/guides/python/editor/add-link-annotations-to-pdf.md) - [Adding redaction annotations to a PDF document](/guides/python/editor/add-redaction-annotations-to-pdf.md) - [Adding shape annotations to a PDF document](/guides/python/editor/add-shape-annotations-to-pdf.md) - [Adding stamp annotations to a PDF document](/guides/python/editor/add-stamp-annotations-to-pdf.md) - [Adding sticky note annotations to a PDF document](/guides/python/editor/add-sticky-note-annotations-to-pdf.md) - [Adding text markup annotations to a PDF document](/guides/python/editor/add-text-markup-annotations-to-pdf.md) - [Adding visible digital signatures to a PDF document](/guides/python/editor/add-visible-signature-to-pdf.md) - [Advanced digital signature workflows](/guides/python/editor/advanced-digital-signatures.md) - [Certifying PDF documents](/guides/python/editor/certify-a-pdf-document.md) - [Detecting and adding form fields to a PDF document](/guides/python/editor/detect-and-add-form-fields.md) - [Editing PDF form fields](/guides/python/editor/editing-pdf-form-fields.md) - [Editing PDF metadata with Nutrient Python SDK](/guides/python/editor/editing-pdf-metadata.md) - [Filling PDF form fields](/guides/python/editor/fill-pdf-form.md) - [Managing PDF page order](/guides/python/editor/manage-pdf-page-order.md) - [Merging PDFs](/guides/python/editor/merge-pdf-into-other-pdf.md) - [Signing PDFs with PAdES levels](/guides/python/editor/sign-pdf-with-pades-level.md)