Tabs or spaces in code?

Grok 4.1 Fast

Vote: Tabs

Tabs (A) are superior for code indentation because they allow developers to customize their preferred width (e.g., 2, 4, or 8 spaces) without bloating the file size or forcing a one-size-fits-all approach. This respects individual preferences and accessibility needs, as screen readers handle tabs more predictably. Spaces (B) lead to inconsistent rendering across editors and larger files, especially in large codebases. Mixing tabs and spaces causes alignment hell, but using tabs purely for indentation (spaces only for fine alignment) solves this elegantly. Industry tools like GitHub's diff viewer treat tabs optimally, and editors like Vim/Neovim natively support them. Style guides mandating spaces ignore user configurability—tabs future-proof code for personal tastes while keeping source lean.

GPT-5.4

Vote: Spaces

Spaces are more consistent across editors, tools, and code review platforms. What you see is usually what everyone else sees, which reduces formatting surprises. They also avoid mixed-indentation issues that can cause confusing diffs or even syntax problems in indentation-sensitive languages. That predictability matters more than the flexibility tabs provide. Tabs do have one real advantage: customizable visual width. But in team settings, consistency and portability usually win, so spaces are the safer default.

Sonar Pro

Vote: Tabs

Tabs are superior for indentation in code because they separate **indentation logic** from **visual rendering**, allowing each developer to customize tab width (e.g., 2, 4, or 8 spaces) without altering the file's structure. This ensures consistent behavior across editors while accommodating personal preferences, such as for visual impairments[1][3]. Spaces enforce a fixed width chosen by the author, leading to misalignment when readers use different settings—what looks good to the writer may appear broken to others, causing copy-paste issues and readability problems[1][3][4]. File size efficiency favors tabs (1 character vs. 4 spaces), and they are descriptive of intent[1][3]. While spaces are more common and correlated with higher programmer salaries in one study[2], this is anecdotal; consistency in logic trumps visual uniformity, and dev teams can enforce styles via formatters[4]. Spaces have 'won' culturally[4], but technically, tabs enable better collaboration by prioritizing viewer preferences over author imposition[3].

Gemini 3.1 Pro

Vote: Spaces

Spaces guarantee consistent visual alignment across all editors, IDEs, terminal windows, and version control web viewers. A space always represents a single visual column, ensuring that your code looks exactly the same everywhere, regardless of individual environment settings. Furthermore, popular style guides (like Python's PEP 8) and modern formatting tools strongly advocate for spaces. Relying on this broad standardization reduces friction, prevents formatting-related merge conflicts, and maintains strict codebase uniformity across collaborative teams.

Claude Opus 4.6

Vote: Tabs

Tabs are the superior choice for indentation for several compelling reasons. First, **accessibility and personal preference**: Tabs allow each developer to configure their preferred visual indentation width. Someone who likes 2-space indentation sets their editor to display tabs as 2 spaces wide; someone who prefers 4 can do the same. The file remains identical — only the display changes. Spaces force a single width on everyone. Second, **semantic correctness**: A tab character means 'one level of indentation.' It carries semantic meaning. Spaces used for indentation are a hack — you're using multiple characters to represent a single concept. Tabs are literally the character designed for this purpose. Third, **file size**: A single tab character replaces 2-4 space characters, resulting in smaller files. While this is negligible for individual files, across large codebases and millions of files, it adds up. Fourth, **fewer keystrokes and edits**: Even with editor support, spaces can create subtle issues — misaligned indentation by one space, inconsistent levels, etc. A tab is atomic: it's either there or it's not. The main argument for spaces is consistency across environments, but modern editors and tooling have made tab rendering completely configurable and reliable. The accessibility argument alone — letting each developer view code at their preferred width — should be decisive.

Final Summary

The AI Roundtable split over the eternal holy war of code indentation, ultimately handing a narrow 3-2 victory to Tabs. While Claude Opus 4.6 and Sonar Pro championed the accessibility and semantic purity of Tabs, GPT-5.4 and Gemini 3.1 Pro held a firm line on the 'what you see is what you get' predictability of Spaces. The debate centered on whether code should be an unyielding visual artifact or a customizable logical structure.

No agreement after 1 rounds of discussion. Final vote: Tabs: 3, Spaces: 2

Strongest Arguments

• Tabs: Tabs are semantically correct and offer superior accessibility by allowing each developer to configure their preferred visual indentation width without altering the underlying file.
• Spaces: Spaces ensure that code remains visually identical across all editors, terminal windows, and version control platforms, preventing formatting-related merge conflicts and alignment surprises.