diff --git a/lua/guid.lua b/lua/guid.lua
index 31ae37f..5e8c6b5 100644
--- a/lua/guid.lua
+++ b/lua/guid.lua
@@ -12,6 +12,23 @@ local function insert_text_at_pos(text, pos)
     vim.fn.setline(pos.row, prefix .. text .. suffix)
 end
 
+local function find_pattern(pattern, flags)
+    local row, col = unpack(vim.fn.searchpos(pattern, flags))
+    if row ~= 0 or col ~= 0 then
+        local text = vim.fn.matchstr(vim.fn.getline(row), pattern)
+        return {row = row, col = col, text = text}
+    end
+end
+
+local function find_pattern_at_pos(pattern, pos)
+    for _, flags in ipairs({'cnW', 'bnW'}) do
+        local match_pos = find_pattern(pattern, flags)
+        if match_pos and match_pos.row == pos.row and match_pos.col <= pos.col and match_pos.col + #match_pos.text > pos.col then
+            return match_pos
+        end
+    end
+end
+
 local function guid_generate()
     local bytes = {}
     for i = 1, 16 do
@@ -20,6 +37,19 @@ local function guid_generate()
     return bytes
 end
 
+local function guid_parse(text)
+    local text_stripped = text:gsub('[-]', '')
+    assert(#text_stripped == 32)
+
+    local bytes = {}
+    for i = 0, 30, 2 do
+        local text_byte = text_stripped:sub(1 + i, 2 + i)
+        table.insert(bytes, tonumber(text_byte, 16))
+    end
+
+    return bytes
+end
+
 local function guid_print(guid, style)
     if style == '' then
         style = 'd'
@@ -55,6 +85,8 @@ local function guid_print(guid, style)
     return guid_printed
 end
 
+-- [465a78ad-93cc-732e-a836-9824d49506d6]
+
 local function guid_insert(style)
     local pos = get_cursor_pos()
     local guid = guid_generate()
@@ -62,8 +94,25 @@ local function guid_insert(style)
     insert_text_at_pos(guid_printed, pos)
 end
 
-local function guid_format()
+local function guid_format(style)
+    local pos = get_cursor_pos()
+    local patterns = {
+        '[0-9a-fA-F]\\{8\\}-[0-9a-fA-F]\\{4\\}-[0-9a-fA-F]\\{4\\}-[0-9a-fA-F]\\{4\\}-[0-9a-fA-F]\\{12\\}'
+    }
 
+    for _, pattern in ipairs(patterns) do
+        local match_pos = find_pattern_at_pos(pattern, pos)
+        if match_pos then
+            local guid = guid_parse(match_pos.text)
+            local line = vim.fn.getline(pos.row)
+            ---@diagnostic disable-next-line: undefined-field
+            local line_prefix = line:sub(1, match_pos.col - 1)
+            ---@diagnostic disable-next-line: undefined-field
+            local line_suffix = line:sub(match_pos.col + #match_pos.text)
+            vim.fn.setline(match_pos.row, line_prefix .. guid_print(guid, style) .. line_suffix)
+            return
+        end
+    end
 end
 
 return {