notebook lens

JetBrains Marketplaceplugin 33811free viewer, Pro subscription

Install from the JetBrains Marketplacefree to read; the Pro trial runs 30 days

The kernel is dead; the outputs are not. They read as they were saved, with no code run, and a 175 MB notebook of 9,000 cells opens in about a second.

Notebook Lens reads a Jupyter notebook as a document in IntelliJ IDEA and the other JetBrains IDEs, with no kernel behind it, and it needs nothing else installed before it works. It indexes where each cell begins rather than loading the file whole, so a 175 MB notebook with 9,000 cells, images and long outputs is open in about a second, and Go to cell lands on cell 9,000 directly. Outputs appear as they were saved, and no code runs while you read. With Pro you can compare two notebooks with the outputs left out, search every cell in one pass, and export the source to .py or Markdown, or the whole notebook to one HTML page.

opens

.ipynb notebooks; a legacy nbformat 3 file is named, with the exact convert command

runs on

IntelliJ IDEA, GoLand, Android Studio, PyCharm, WebStorm, Rider and every JetBrains IDE from 2024.2 on

store

JetBrains Marketplace, plugin 33811

newest version

1.3.1, published 2026-10-27

pro

a subscription with its own 30-day trial; the price is quoted below as the store shows it

A notebook file is JSON underneath, and the parser that reads it is our own, with no third-party reader behind it.

price, as the store shows it

The viewer is free and stays free. Pro is a subscription for this plugin: USD 2.90 a month or USD 29 a year for individual use. For organizations it is, per user, USD 5.80 a month or USD 58 a year.

where it stops

• No execution and no kernels; a cell's source can be changed, and its outputs stay as the last run printed them, under the mark "outputs from the previous run"
• Markdown tables and LaTeX appear as source rather than rendered wrongly
• nbformat 3 files are named, not half-read

what's new

• 1.3.1published 2026-10-27

  The 1.3.0 cut, uploaded a second time; nothing in the plugin changed.

• 1.2.9published 2026-10-25

  A markdown paragraph with two underscores in it, such as inline math ($L_{train}$ and $L_{val}$) or two snake_case names (user_id and order_id), lost both underscores and showed the text between them in italics, in the viewer and in the exported HTML page. Both now show as written. Math between dollar signs, \( \) or \[ \] keeps its source, and a line starting \begin{ shows as LaTeX source the way a $$ block does. Any other backslash before a punctuation mark shows the mark, and text in __double underscores__ is bold, as Jupyter shows them.

• 1.2.8published 2026-10-22

  An execution count past what a 64-bit number holds reads "Number too long" in the viewer, where 1.2.7 raised an IDE error. A notebook that shrinks or changes on disk while it is open no longer raises an error: a search over it ends with "Search stopped - nothing was listed." and the reason, and an export of it fails with that reason and leaves no file, where the export wrote the cells it could still read. An empty file reads "Not a notebook: the file is empty (0 bytes)." A notebook saved as UTF-16 says so and asks to save it as UTF-8. A JSON Lines file opened as a notebook is named as one. Overlong UTF-8 shows as the replacement character. An nbformat number past the int range reads as unknown instead of as its low bits.

more

• every format, every product
• opening a large file
• the exports
• support

Pricing, invoices and licensing questions go to sales@twilightventures.dev; anything else about the product to support@twilightventures.dev.