package ocamlformat

  1. Overview
  2. Docs
Auto-formatter for OCaml code

Install 

dune-project
 Dependency

github.com Readme Changelog Edit opam file Versions (19)

Authors

  1. J
    Josh Berdine <jjb@fb.com>
  2. H
    Hugo Heuzard <hugo.heuzard@gmail.com>
  3. E
    Etienne Millon <etienne@tarides.com>
  4. G
    Guillaume Petiot <guillaume@tarides.com>
  5. J
    Jules Aguillon <jules@j3s.fr>

Maintainers

  1. G
    Guillaume Petiot <guillaume@tarides.com>
  2. J
    Jules Aguillon <jules@j3s.fr>
  3. E
    Emile Trotignon <emile@tarides.com>

Sources

ocamlformat-0.29.0.tbz
sha256=dac77f0a957ae782bb4b869b07b9803a872a34f8c1eae8901b42d21b623c9db5
sha512=b4ae6fda3c28e91dc12411b577df7b216e9b1afe5887bcb9e89c158e1313dc92183c29ffb256f47f5c9384af3ac8c505ec76849b26ae950b82c9b4c21a460819

Description

ocamlformat is a code formatter for OCaml. It comes with opinionated default settings but is also fully customizable to suit your coding style.

  • Profiles: ocamlformat offers profiles we predefined formatting configurations. Profiles include default, ocamlformat, janestreet.
  • Configurable: Users can change the formatting profile and configure every option in their .ocamlformat configuration file.
  • Format Comments: ocamlformat can format comments, docstrings, and even code blocks in your comments.
  • RPC: ocamlformat provides an RPC server that can be used by other tools to easily format OCaml Code.

Published: 18 Mar 2026

README

ocamlformat

OCaml Code Formatter.

OCaml-CI Build Status

ocamlformat is a code formatter for OCaml. It comes with opinionated default settings but is also fully customizable to suit your coding style.

  • Profiles: ocamlformat offers profiles we predefined formatting configurations. Profiles include default, ocamlformat, janestreet.
  • Configurable: Users can change the formatting profile and configure every option in their .ocamlformat configuration file.
  • Format Comments: ocamlformat can format comments, docstrings, and even code blocks in your comments.
  • RPC: ocamlformat provides an RPC server that can bed used by other tools to easily format OCaml Code.

ocamlformat is part of the OCaml Platform, the recommended set of tools for OCaml.

Getting Started

Installation

To use ocamlformat, you will need OCaml and opam (the OCaml package manager) installed on your system. Visit the OCaml.org installation page for instructions.

With OCaml and opam installed, you can install ocamlformat with:

opam install ocamlformat

Usage

Formatting your code is as easy as running:

ocamlformat file.ml

To configure ocamlformat to your liking, create an .ocamlformat configuration file in your project with settings like:

profile = default
version = 0.29.0

Refer to our documentation or use ocamlformat --help for a full list of configuration options.

To make formatting your code even easier, use the dune build system:

dune fmt

Documentation

The full documentation for ocamlformat, including comprehensive user and API guides, can be found on OCaml.org.

Contributing

Contributing Guide

We wholeheartedly welcome contributors! To start, please read our Contributing Guide to familiarize yourself with our development process, including how to propose and how to start hacking on ocamlformat.

Hacking Guide

In addition to the Contributing Guide, we provide a Hacking Guide for ocamlformat developers. It contains in-depth explanation of development processes, such as running tests, releasing ocamlformat, etc.

Code of Conduct

In order to foster a welcoming and respectful community, ocamlformat has adopted the OCaml Code of Conduct.

Roadmap

Interested in the future of ocamlformat? Take a look at our Roadmap to understand our vision and planned advancements for ocamlformat.

Discussions

For conversations on ongoing development, be sure to visit the ocamlformat section of the OCaml Discuss forum.

License

ocamlformat is distributed under the terms of the MIT License. See the LICENSE file for complete details.

Acknowledgments

We gratefully acknowledge the individuals and organizations that have significantly contributed to ocamlformat.

ocamlformat owes its existance to its initial author, Josh Berdine. We also want to express our appreciation to Hugo Heuzard, Guillaume Petiot, and Jules Aguillon. Their significant contributions have been instrumental to the advancement of ocamlformat.

Moreover, our gratitude extends to Facebook, who fostered the inception of ocamlformat as part of their work on the ReasonML project. Jane Street and Tarides have also provided financial support and contributed to the ongoing development of the project.

Dependencies (5)

  1. re >= "1.10.3"
  2. ocamlformat-lib = version
  3. dune >= "2.8"
  4. csexp >= "1.4.0"
  5. ocaml >= "4.08"

Dev Dependencies (4)

  1. odoc with-doc
  2. ocamlformat-rpc-lib with-test & = version
  3. dune < "3.22" & with-test
  4. cmdliner with-test = "false" & >= "1.1.0" | with-test & >= "1.2.0"

  1. ask
  2. ask-integrator
  3. autofonce
  4. autofonce_config
  5. autofonce_core
  6. autofonce_lib
  7. autofonce_m4
  8. autofonce_misc
  9. autofonce_patch
  10. autofonce_share
  11. awskit >= "0.2.0"
  12. awsm-codegen
  13. bastet < "2.0.0"
  14. bitpack_serializer
  15. brisk-reconciler
  16. CamelCase
  17. canary >= "0.0.4"
  18. claudius
  19. coap
  20. coap-core
  21. coap-server-lwt
  22. diff
  23. diskuvbox < "0.2.0"
  24. dream-inertia
  25. drom
  26. drom_lib
  27. drom_toml
  28. dump_ocamlformat
  29. dune_deps_extra
  30. ephemeral
  31. ez_cmdliner >= "0.2.0"
  32. ez_config >= "0.2.0"
  33. ez_file >= "0.2.0" & < "0.5.0"
  34. ez_hash < "0.5.3"
  35. ez_opam_file
  36. ez_search
  37. ez_subst
  38. fromager
  39. giflib
  40. guardian != "0.1.0"
  41. header-check
  42. hegel
  43. html_of_jsx >= "0.0.6"
  44. js_of_ocaml-webgpu >= "0.2"
  45. letters >= "0.2.0" & != "0.3.1"
  46. lunar
  47. melange-fest
  48. melange-fetch >= "0.2.0"
  49. melange-json >= "1.2.0"
  50. melange-radix-icons >= "0.1.0"
  51. melange-str
  52. mlx
  53. module-graph
  54. mqtt
  55. nel
  56. noCanren
  57. object
  58. ocaml-lsp-server < "1.9.0"
  59. ocamlmerlin-mlx >= "0.11"
  60. ochre
  61. ocp-search
  62. ocplib_stuff >= "0.3.0"
  63. oktree
  64. opam-bin >= "0.9.5"
  65. opam_bin_lib >= "0.9.5"
  66. owi >= "0.2"
  67. parseff
  68. pgn_to_tex
  69. pidgin
  70. polars
  71. polars_async
  72. ppx_deriving_jsonschema
  73. ppx_deriving_melange
  74. ppx_mixins
  75. prelude >= "0.4"
  76. primavera
  77. psmt2-frontend >= "0.3.0"
  78. query-json
  79. quickjs >= "0.2.0"
  80. raylib >= "2.0.0"
  81. rea < "0.2.0"
  82. react-rules-of-hooks-ppx
  83. red-black-tree
  84. scope
  85. signal
  86. sihl < "0.1.0"
  87. slugline
  88. smtml >= "0.10.0"
  89. solidity-alcotest
  90. solidity-common
  91. solidity-parser
  92. solidity-test
  93. solidity-typechecker
  94. soteria
  95. spectrum >= "0.7.0"
  96. sqids
  97. styled-ppx
  98. symex
  99. synchronizer
  100. tabr
  101. virtfs
  102. yocaml >= "2.0.0"
  103. zanuda < "1.1.0"

Conflicts

None