How This grep Command Builder Works
Toggle the options you want, recursive search, case insensitivity, invert match, line numbers, context lines, include or exclude globs, and this grep command generator assembles a copy-ready command as you go, along with a plain-English explanation of what each flag does. Use it to build grep command online output ready to paste straight into a terminal, no local installation or man page lookup required. Switch the Tool selector between grep, rg (ripgrep), and ag, and the same set of options re-renders using that tool's actual flag syntax, so it doubles as a silver searcher command builder whenever ag is selected, since a ripgrep command builder and a plain grep command generator don't always agree on what a given behavior is called. Both a single-line command and a multi-line, backslash-continued version are generated, so pasting into a shell script reads as cleanly as pasting into a one-off terminal command.
grep vs ripgrep vs ag: Which Should You Use
The grep vs ripgrep vs ag question mostly comes down to speed and defaults, not fundamentally different capability. grep is installed nearly everywhere by default and its behavior is the most portable, but it's the slowest of the three on large trees and needs an explicit -r to recurse into directories. ripgrep (rg) is written in Rust, recurses by default, automatically skips files ignored by .gitignore, and is typically the fastest of the three on real codebases, which is why it's become the default "just search everything" tool for a lot of developers. ag (the Silver Searcher) sits in between, faster than grep, also recurses and respects .gitignore by default, though it's seen less active development in recent years than ripgrep. This rg command generator and grep command generator share one interface specifically so switching between them is a one-click comparison rather than a rewrite.
| Tool | Recursive by default | Respects .gitignore | Typically installed by default |
|---|---|---|---|
| grep | No (needs -r) | No | Yes, on nearly every Unix-like system |
| ripgrep (rg) | Yes | Yes | No, usually installed separately |
| ag (Silver Searcher) | Yes | Yes | No, usually installed separately |
Common grep Flags Explained
Every flag toggled in this tool gets a one-line explanation printed alongside the generated command, but the table below is a quick grep flags explained reference for the ones that come up most. Not every flag exists identically across all three tools, ag in particular only exposes a smaller subset here (no separate include/exclude glob flags, max match count, or symlink following), since its own flag set diverges further from grep's than ripgrep's does.
| Flag (grep) | Meaning | Equivalent in rg |
|---|---|---|
| -r | Recursively search directories | default behavior (or --no-recursive to disable) |
| -i | Ignore case distinctions | -i |
| -v | Select lines NOT matching the pattern | -v |
| -w | Match whole words only | -w |
| -x | Match whole lines only | no direct equivalent, anchor the pattern with ^ and $ |
| -n | Show line numbers | -n |
| -c | Print a count of matching lines only | -c |
| -l | Print file names with matches only, not the matches | -l |
| -C n | Show n lines of context around each match | -C n |
| -F | Treat the pattern as a fixed string, not a regex | -F |
| --include / --exclude | Only search, or skip, files matching a glob | -g "pattern" / -g "!pattern" |
Common Uses
Searching a codebase recursively for TODO or FIXME comments, building a recursive grep command that's case insensitive for a quick keyword hunt, counting how many lines in a log file match an error pattern, and listing just the filenames that contain a pattern (for piping into another command) are the most common uses of a grep command builder. Context lines are useful for seeing a few lines of surrounding code around each match without opening every file, and the NUL-separator option exists specifically for safely piping filenames with spaces or special characters into xargs -0.
What This Tool Doesn't Do
This tool builds the command text, it doesn't execute it, so no files on your machine or any server are actually searched, and no regex syntax validation happens beyond what's needed to assemble the flags. It also doesn't cover every flag each tool supports, grep, rg, and ag each have dozens of additional options beyond what's exposed here, this grep syntax generator focuses on the flags used in the overwhelming majority of everyday searches rather than being an exhaustive reference for every edition of every tool.