BaseJump

Convert numeric literals between bases directly in the editor. BaseJump detects the base of the number at the cursor — or every number across multiple cursors and block selections — and presents all valid conversions in a quick-pick menu. Replace in place or copy to the clipboard.

Best Practices: Always Prefix Your Numeric Literals

Numeric literals without a base prefix are inherently ambiguous. Consider the value 255:

• As decimal: it's the number two hundred and fifty-five
• As hexadecimal: it represents decimal 597
• As binary: it would be invalid (contains digits > 1), but 11111111 without a prefix looks like decimal 11,111,111 or hex 286,331,153

When BaseJump encounters a literal without a prefix, it has to guess — or ask. If the value is unambiguously one base (e.g. has 'A'-'F') it will auto-detect hex. If multiple bases are plausible, it will prompt you to clarify intent before converting. The less ambiguous your input, the cleaner the experience: fewer prompts, a shorter conversion menu, and no second-guessing.

Recommendation: always use base prefixes.

BaseJump's Assume Binary and Assume Decimal settings exist to help when you're working with legacy code or pasted values that lack prefixes — but they are workarounds for a problem that prefixes eliminate entirely. When in doubt, prefix it.

Features

• Automatic base detection — recognizes hexadecimal (0x), binary (0b), octal (0o/leading-zero), and decimal literals, with and without digit-group separators.
• Interactive conversion — the Convert Number command opens a quick-pick showing every valid target base for the token at the cursor. Select a conversion to apply it.
• Digit-group separators — results can include nibble separators for binary (0b1010'1010), byte separators for hex (0xFF'AA), and thousands separators for decimal (1'000'000).
• Language-aware delimiters — the separator character matches the convention for the active file's language (C/C++ → ', Python/Rust/Java/Go/Kotlin/Swift → _, Markdown/plain text → space). Fully overridable per-language in settings.
• Toggle Delimiters — add, remove, or switch the digit-group separators on an existing literal in one command.
• Whole-file conversion — the Convert Editor Content command scans the entire document and converts every compatible token in one operation, using a quick-pick to choose the target base. Great when you paste in a bunch of numbers for conversion in a temporary editor.
• Favorites — star any conversion in the quick-pick to pin it at the top for fast access. Favorites are remembered across sessions.
• Block selection — select a range of text and run Convert Number or a direct command; BaseJump scans the selected block for all individual tokens and converts every one in a single operation.
• Multi-cursor and multi-selection — all active cursors and block selections are processed simultaneously.
• Copy or replace — choose whether conversions replace the token in the editor or copy the result to the clipboard. Per-item copy and replace buttons in the quick-pick let you override the default for any individual conversion on the fly.
• Insert note — the comment button (📝) in the quick-pick inserts a comment line immediately above the token's line, using language-appropriate comment syntax, with the original value and its conversion. For example, in a C++ file: // BaseJump: 255 = 0xFF. Supports //, #, --, <!-- -->, and /* */ styles across all common languages.

Context Menu Configuration

Right-clicking in any editor shows BaseJump commands. Both the layout and which commands appear are fully configurable.

Layout: Submenu vs. Top Level

The basejump.contextMenuLayout setting controls how BaseJump appears in the context menu.

submenu (default) — all enabled commands are grouped under a single collapsible BaseJump entry:

  ─────────────────────────────
  ▶ BaseJump
      Convert Number
      Convert Editor Content
      Toggle Delimiters
  ─────────────────────────────

This keeps the context menu clean and uncluttered, especially if you rarely use BaseJump from the menu.

topLevel — each enabled command appears directly in the context menu, visually separated from other menu items by divider lines:

  ─────────────────────────────
  Convert Number
  Convert Editor Content
  Toggle Delimiters
  ─────────────────────────────

This is useful if you use BaseJump frequently and want one-click access without the extra submenu hop.

none — BaseJump does not appear in the context menu at all. Use the Command Palette (BaseJump: category) or keyboard shortcuts instead. This is ideal for keyboard-first workflows where the context menu is rarely used and you prefer to keep it as minimal as possible.

Per-Command Visibility

Each command can be shown or hidden independently of the layout mode:

Convert Number is the all-in-one option: one menu entry, any conversion, chosen via quick-pick. Use it for a minimal menu. The explicit conversion commands (Convert to Binary, Convert to Hex, etc.) give you finer-grained control — enable whichever targets you want to appear directly in the menu, and disable Convert Number if you prefer everything to be one click away.

Note: If all commands are disabled, no BaseJump entry will appear in the context menu at all (equivalent to setting contextMenuLayout to none). All commands remain fully accessible via the Command Palette and any keyboard shortcuts you have assigned.

Note: Hiding a command from the context menu does not disable it — it remains fully available in the Command Palette and can still be bound to a keyboard shortcut.

Commands and Keyboard Shortcuts

All BaseJump commands are available in the Command Palette under the BaseJump: category. There are no default keyboard shortcuts — to assign one, open Preferences → Keyboard Shortcuts and type BaseJump in the filter bar to see all available commands.

The direct-conversion commands (convertToBinary, convertToHex, etc.) are well suited for keyboard shortcuts — they operate immediately on the token at the cursor(s) or selected block(s) only opening a menu if source bases are ambiguous.

Insert Comment

The Insert Comment action inserts a language-appropriate comment line immediately above the token's line, showing the original value and its converted form. For example, in a C++ file:

// BaseJump: 255 = 0xFF
uint8_t mask = 255;

The inserted comment is indented to match the line it annotates.

Triggering Insert Comment

There are two ways to insert a comment:

• Comment button — click the 💬 button on any item in the Convert Number quick-pick. This works regardless of the defaultAction setting.
• Default action — set "basejump.defaultAction": "insertComment" in your settings, then pressing Enter on any quick-pick item inserts a comment instead of replacing or copying.

Language Comment Styles

BaseJump selects the comment syntax based on the active file's language:

Falls back to // comment for unrecognized languages.

Multi-Cursor Behavior

When multiple cursors or a block selection produce tokens on the same line, only one comment is inserted for that line (listing all the conversions from that line). Tokens on different lines each get their own comment. Comments are inserted in reverse line order so that earlier line numbers are not displaced by insertions above them.

Settings

The basejump.fallbackDelimiter setting is language-overridable, so you can set a different separator per language in your settings.json:

"[python]": {
  "basejump.fallbackDelimiter": "underscore"
}

Built-in language defaults (applied automatically without any configuration): C/C++ → ', Python/Rust/Java/Go/Kotlin/Swift → _. Markdown and plain text files have no built-in default and use the fallbackDelimiter setting like any other unlisted language.

Special case — Decimal (thousands) with space delimiter: If you explicitly configure fallbackDelimiter to space and convert to Decimal (thousands), BaseJump automatically uses the system locale's thousands separator instead (typically , on en-US or . on European locales), since space-separated digit groups like 1 000 000 are ambiguous and unfamiliar to most readers.

Note — No delimited octal variant: Octal lacks a universally recognized digit-group separator. The natural grouping (every 3 or every 4 digits) is inconsistent across languages and tools, and no convention has emerged the way nibbles have for binary or bytes for hex. Rather than invent one, BaseJump omits the delimited octal option entirely.

License

See LICENSE for details.

AI Disclaimer

• YES This extension was 100% vibe coded, including project scaffolding, design, icons, implementation, test, and documentation. The only exception might be this AI Disclaimer section.
• YES I have 40 years of SW Dev experience that I lean on to "Guide the Vibe (tm)".
• NO I have not looked at the code...at all. It might be a hairy scary mess in there but all my tests pass. And I keep the tests up to date.
• YES I wrote this extension primarily for myself and my team at work to help us be more productive because we deal in hex, binary and decimal constants all the time (not so much octal though...)