"CSVI" - Terminal CSV Editor

<English> / <Japanese>

CSVI is a terminal-based CSV editor for UNIX-like systems and Windows.

✨ Key Features

• Minimal changes on save
  CSVI keeps the original formatting for every unmodified cell: quotes, line endings (LF/CRLF), BOM, encoding, and field/record separators.
  Only actual edits are saved—making it ideal for clean diffs and safe edits to production data.

• vi-style and Emacs-style keybindings
  Move the cursor like in vi, and edit cells like in Emacs.

• Reads from both file and standard input
  You can pipe CSV data into CSVI or open a file directly.

• Fast startup and background loading
  Opens large files quickly without blocking the interface.

• Visual feedback for edits
  Modified cells are underlined.
  Press u to undo a cell's change and restore its original value.

• Shows original format details
  The bottom line of the screen shows technical info: quoting, encoding, field separators, and more—just as they appeared in the original file.

• Flexible encoding support

  • UTF-8 (default)
  • UTF-16
  • Current Windows code page (auto-detected)
  • Any encoding from the IANA registry using -iana NAME

• Color scheme options

  • Default colors assume a dark background.
  • Use -rv for light backgrounds, or set NO_COLOR to disable color output (https://no-color.org/ )

Video by @emisjerry

Install

Manual Installation

Download the binary package from Releases and extract the executable.

⚠️ Note: The macOS build is experimental and not yet tested. Please let us know if you encounter any issues!

Use "go install"

go install github.com/hymkor/csvi/cmd/csvi@latest

Use scoop-installer (Windows only)

scoop install https://raw.githubusercontent.com/hymkor/csvi/master/csvi.json

or

scoop bucket add hymkor https://github.com/hymkor/scoop-bucket
scoop install csvi

Usage

$ csvi {options} FILENAME(...)

or

$ cat FILENAME | csvi {options}

Options

• -help this help
• -h int the number of fixed header lines
• -c use Comma as field-separator (default when suffix is .csv)
• -t use TAB as field-separator (default when suffix is not .csv)
• -semicolon use Semicolon as field-separator
• -iana string IANA-registered-name to decode/encode NonUTF8 text
• -16be Force read/write as UTF-16BE
• -16le Force read/write as UTF-16LE
• -auto string auto pilot (for testcode)
• -nonutf8 do not judge as UTF-8
• -w widths set the widths of cells (e.g., -w 14,0:10,1:20 to set the first column to 10 characters wide, the second column to 20 characters wide, and all others to 14 characters wide)
• -fixcol forbid insertion or deletion of cells (disables i, a, and x)
• -p Protect the header line
• -readonly Read Only Mode
• -rv Enable reverse-video display (invert foreground and background colors)

Key-binding

• Move Cursor
  • h,Ctrl-B,←,Shift-TAB (move cursor left)
  • j,Ctrl-N,↓,Enter (move cursor down)
  • k,Ctrl-P,↑ (move cursor up)
  • l,Ctrl-F,→,TAB (move cursor right)
  • < (move the beginning of file)
  • >,G (move the end of file)
  • 0,^,Ctrl-A (move the beginning of the current line)
  • $,Ctrl-E (move the end of the current line)
• Search
  • / (search forward for a partial match)
  • ? (search backward for a partial match)
  • n (repeat the previous search forward)
  • N (repeat the previous search backward)
  • * (search forward for the next cell that exactly matches the current one)
  • # (search backward for the previous cell that exactly matches the current one)
• Edit
  • i (insert a new cell before the current one)
  • a (append a new cell after the current one)
  • r (replace the current cell)
  • d,x (delete the current cell)
  • w (write to a file or STDOUT('-'))
  • o (append a new line after the current one)
  • O (insert a new line before the current one)
  • D (delete the current line)
  • " (enclose or remove double quotations if possible)
  • u (restore the original value of the current cell)
  • y (copy the value of the current cell to kill-buffer)
  • p (paste the value of kill-buffer to the current cell)
• Display settings
  • L (reload the file using a specified encoding)
  • Ctrl-L (Repaint)
  • ] (widen the column at the cursor)
  • [ (narrow the column at the cursor)
• Quit: q or ESC

Environment Variables

NO_COLOR

If the environment variable NO_COLOR is set to any value with at least one character, csvi disables colored output. This follows the standard proposed by NO_COLOR.

RUNEWIDTH_EASTASIAN

Specifies the display width for Unicode characters classified as ambiguous width.

• Double-width: set RUNEWIDTH_EASTASIAN=1
• Single-width: set RUNEWIDTH_EASTASIAN=0 (any non-1 value with at least one character is also valid)

COLORFGBG

When the environment variable is defined in the form (FG);(BG) and the foreground (FG) is less than the background (BG), csvi automatically uses color settings suitable for light backgrounds (equivalent to the -rv option).

csvi normally uses the terminal's default colors via the escape sequences ESC[39m and ESC[49m. Thus, the (FG);(BG) values are not directly applied; they are only used to determine whether gray background lines should be adjusted toward light or dark shades.

GOREADLINESKK

When the environment variable GOREADLINESKK specifies dictionary files, the built-in SKK¹ Kana-to-Kanji conversion via go-readline-skk is enabled.

• Windows

  • set GOREADLINESKK=SYSTEMJISYOPATH1;SYSTEMJISYOPATH2...;user=USERJISYOPATH
  • Example: set GOREADLINESKK=~/Share/Etc/SKK-JISYO.L;~/Share/Etc/SKK-JISYO.emoji;user=~/.go-skk-jisyo

• Linux

  • export GOREADLINESKK=SYSTEMJISYOPATH1:SYSTEMJISYOPATH2...:user=USERJISYOPATH

(Note: ~ is automatically expanded to %USERPROFILE% on Windows, even in cmd.exe.)

Use as a Go package

package main

import (
    "fmt"
    "os"
    "strings"

    "github.com/mattn/go-colorable"

    "github.com/hymkor/csvi"
    "github.com/hymkor/csvi/uncsv"
)

func main() {
    source := `A,B,C,D
"A1","B1","C1","D1"
"A2","B2","C2","D2"`

    cfg := &csvi.Config{
        Mode: &uncsv.Mode{Comma: ','},
    }

    result, err := cfg.Edit(strings.NewReader(source), colorable.NewColorableStdout())

    if err != nil {
        fmt.Fprintln(os.Stderr, err.Error())
        os.Exit(1)
    }

    // // env GOEXPERIMENT=rangefunc go run example
    // for row := range result.Each {
    //     os.Stdout.Write(row.Rebuild(cfg.Mode))
    // }
    result.Each(func(row *uncsv.Row) bool {
        os.Stdout.Write(row.Rebuild(cfg.Mode))
        return true
    })
}

Release Note

• English
• Japanese

Acknowledgements

• sergeevabc (Aleksandr Sergeev) — Issue #1
• kevin-gwyrdh (Kevin) — Issue #4
• emisjerry (emisjerry) — YouTube video
• rinodrops (Rino) — Discussion #5

Author

• hymkor (HAYAMA Kaoru)