# mozilla-firefox/firefox SLOC report

> As of 2026-10-06 (commit 0a663c251191), mozilla-firefox/firefox contains 35,179,649 total lines: 24,533,926 code, 7,006,855 comments, 3,638,868 blank, across 139,689 files in 91 languages (top: C++ 22.7%). Custom configuration (tests excluded, docs excluded, generated excluded). Counted with tokei via OctoCounts.

mozilla-firefox/firefox has 24,533,926 source lines of code out of 35,179,649 total lines across 139,689 files, counted from the main ref at commit 0a663c251191 by the OctoCounts tokei engine on 2026-10-06. The report is cached by commit, tokei version, and analysis options, so recounting the same revision returns exactly these numbers.

OctoCounts produced this report by resolving mozilla-firefox/firefox to commit 0a663c251191, downloading the repository source archive, and counting every source file with tokei, the open-source line counter written in Rust. The table below breaks the count down by programming language into files, total lines, code lines, comment lines, and blank lines, so the figures can be compared across languages and projects. Results are cached by commit, tokei version, and analysis options, so counting the same revision again reproduces exactly these numbers.

## Repository size insights

This is a very large codebase by counted code lines. Code represents 69.7% of all lines, comments represent 19.9%, and the repository averages 176 code lines per file. C++ accounts for 22.7% of counted code.

| Language | Files | Lines | Code | Comments | Blanks |
| --- | ---: | ---: | ---: | ---: | ---: |
| C++ | 13,136 | 7,317,824 | 5,576,440 | 809,106 | 932,278 |
| Rust | 12,693 | 4,893,931 | 4,305,047 | 207,563 | 381,321 |
| C Header | 19,609 | 5,011,944 | 3,123,220 | 1,231,535 | 657,189 |
| C | 3,713 | 3,890,481 | 2,877,755 | 635,572 | 377,154 |
| JavaScript | 6,201 | 2,675,377 | 1,999,191 | 442,498 | 233,688 |
| Python | 4,938 | 1,342,457 | 1,075,649 | 89,708 | 177,100 |
| JSON | 1,413 | 1,005,027 | 1,004,576 | 0 | 451 |
| INI | 26,826 | 1,247,625 | 858,014 | 231 | 389,380 |
| C++ Header | 1,405 | 720,731 | 575,728 | 55,842 | 89,161 |
| XML | 6,907 | 857,286 | 453,166 | 387,741 | 16,379 |
| Kotlin | 4,262 | 622,758 | 451,546 | 98,486 | 72,726 |
| HTML | 19,208 | 397,968 | 358,838 | 18,033 | 21,097 |

Top language (C++ 22.7%). Generated at 2026-10-06T17:54:48.366574620+00:00. Canonical report: https://octocounts.com/github/mozilla-firefox/firefox

## Reproduce this report

[Reproduce this exact report and configuration](https://octocounts.com/github/mozilla-firefox/firefox/commit/0a663c2511915210918dc86255360d7d28220c1c?analysis=%7B%22ignoredDirs%22%3A%5B%5D%2C%22ignoredLanguages%22%3A%5B%5D%2C%22profile%22%3A%22default%22%2C%22includeDocs%22%3Afalse%2C%22includeTests%22%3Afalse%2C%22includeGenerated%22%3Afalse%7D).

## Report FAQ

### How many lines of code does mozilla-firefox/firefox have?

mozilla-firefox/firefox has 35,179,649 total lines, including 24,533,926 code lines, 7,006,855 comment lines, and 3,638,868 blank lines.

### How was the mozilla-firefox/firefox line count measured?

OctoCounts resolved the public GitHub repository to commit 0a663c251191, downloaded the source archive, counted it with tokei, and cached the report by commit, tokei version, and analysis options.

### What commit was counted for mozilla-firefox/firefox?

This OctoCounts report was generated from main at commit 0a663c251191 on 2026-10-06T17:54:48.366574620+00:00.

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