Guides · measured July 2026
How to find recently changed files, fast.
You saved it an hour ago. Now you can't find it. “Date modified” should be the easiest search on the machine: you're not even asking for a name, just what did I touch recently. Yet on a real 4.47-million-file drive, asking Windows for everything you changed today can take about 67 seconds, because it opens and reads the date on file after file. Spotlight does it in a breath on a Mac; Windows makes you wait. Here is why the OS is slow at the one search that should be trivial, and how an always-current index turns “what changed in the last hour” into a direct lookup.
TL;DR · the short version
- 01
Windows Search and File Explorer's date-modified filter are only fast inside the small slice of the drive they index. Outside it (most repos, Program Files, other drives) they walk the tree and read dates one file at a time (about 67 seconds median on 4.47M files).
- 02
Sorting a big folder tree by Date modified forces the same work: the shell must read every timestamp before it can sort the first result.
- 03
A whole-drive live index keeps every file's modified time current, so “everything changed in the last hour, today, or this week” is a direct slice, answered in the microsecond-to-millisecond range.
- 04
Freshness is about 1 millisecond: a file you just saved counts as “recently changed” almost immediately (under 30 ms worst case).
- 05
The same index answers for you at the taskbar and for AI agents over MCP, across every repo and folder on the machine, not just your user profile.
The problem, honestly
What “date modified” actually costs.
A recently changed file is any file whose date-modified timestamp (the moment its contents last changed) falls inside a window you care about: the last hour, since lunch, or this week.
That sounds trivial, and on one small folder it is. The catch is where the timestamps live. Each file's date sits next to the file itself, scattered across the disk: there is no single list of “every file, newest first.” So to answer “what changed today,” something has to gather millions of dates from millions of places. How each tool does that gathering is the whole story:
- Windows Search can answer from its index, but only for the folders it indexes (your profile: Documents, Desktop, Downloads). Ask about anything outside that slice and it falls back to walking the filesystem and reading dates folder by folder. That fallback is where the ~67 seconds goes.
- Sorting by Date modified in Explorer has to read every entry's timestamp before it can order them; turn on “search subfolders” over a deep tree and it walks the whole thing first.
- The command line (PowerShell, dir /s) keeps no index at all: it reads the last-write time of every file on every run, so the wait grows with the drive.
None of these is a bug: they are all doing the honest, slow thing. The reason the built-in search is slow is coverage, the same reason it is slow at finding a file by name: Windows Search indexes a slice and walks the rest. For the full menu of ways to search a Windows drive, see how to search every file on Windows. The fix for “what changed” is the same as the fix for “where is it”: keep every file's date in one always-current place.
The picture
A time window over the whole drive. Scanned, or sliced.
Picture the drive as a timeline: older files to the left, this second on the right. “What changed in the last 24 hours” is a bracket near NOW. The built-in has no time-sorted view of the drive, so to find the files inside that bracket it reads the date on all 4.47 million. An index that already carries every date just slices the bracket out.
The two rows do the exact same job with opposite economics. The scanner's cost is set by the size of the disk; the slicer's cost is set by the size of the answer. And because the index is kept current as files change, a file you save right now drops into the window about a millisecond later. The freshest edge of “recently changed” is always already there.
Every way to ask “what changed?”
Five ways to find recent files, and what each one costs.
The first three ship with every Windows machine and share one trait: none keeps a complete, current, time-sorted index of the whole drive, so on a big disk they either miss the file or walk to it. Spotlight shows the fast version is possible, on macOS only. The last keeps the whole drive time-indexed on Windows.
| The method | Where it is | How it finds recent files | Time · 4.47M files |
|---|---|---|---|
| Sort by “Date modified” | Any File Explorer window | Reads every entry's timestamp, then sorts; walks subfolders when search is on | seconds → minutes |
| datemodified: filter | Start menu · Explorer box | Uses the index inside indexed folders; walks and re-checks dates everywhere else | 67 s median |
| PowerShell · dir | The terminal | Reads the last-write time of every file on every run: no index at all | grows with the drive |
| Spotlight “Last modified” | macOS Finder smart folder | Whole-volume index already carries dates: a direct answer (Mac only) | as fast as you type |
| Interlinked | Taskbar app + agent tools | Whole drive time-indexed and kept current: the window is a direct slice | milliseconds |
Methodology: Ryzen 9 9950X3D · 64 GB DDR5 · NVMe · Windows 11 · 4,470,000 files. The 67-second figure is a Windows Search median for a file outside the default indexed folders; the Interlinked figure is a direct index answer, in the same microsecond-to-millisecond band as its 139 µs median filename lookup across 20 queries. The middle rows vary with folder size, so they are given as ranges.
The fast answer
Index the dates. Keep them warm.
Interlinked keeps a live index of every file on the machine (names, contents, and modified dates) and stays current as files change, so “everything changed in the last hour” is a direct slice, never a scan. The comparable direct lookup (a filename query on the same drive) returns in about 85 microseconds (139 µs median across 20 queries). A blink takes roughly 100 milliseconds, so the answer lands more than a thousand times faster than you can blink. And the window is never stale: freshness is about a millisecond, so a save is in the index before the dialog closes.
The worst case for “what changed” is an AI agent: it asks constantly, across every repo, and it can't eyeball a folder. So Interlinked hands the same warm index to any AI client that speaks MCP: one install auto-configures 19 of them (Claude Code, Cursor, Codex, Cline, Continue and more). The file hunt that took Claude Code 6 minutes 57 seconds and 71 tool calls comes back in 16 milliseconds and one call: the same shift, and the reason file search is the backbone of the LLM economy.
FAQ · what people ask
Recently changed files, answered.
How do I find files modified today on Windows?
In File Explorer, type datemodified:today into the search box, or click the Date modified column header to sort. Both lean on the index for indexed folders and fall back to walking the tree elsewhere, so a whole-machine “today” query on a large drive can take tens of seconds. A whole-drive index answers the same question in milliseconds.
Why is sorting by “Date modified” so slow on big folders?
To sort by date, the shell must first read the timestamp of every item in scope. With “search subfolders” on, that means walking the whole tree and reading millions of dates before it can show even the first result. The cost scales with the size of the folder, not the difficulty of the question.
Can I search recently changed files across my whole drive, including other repos and git-ignored files?
Not with the built-in tools by default: they index a slice of the drive. A whole-machine index covers every file: every repo, downloads, documents, and the git-ignored files a project-scoped search never sees. “What changed anywhere in the last hour” becomes one lookup.
Does Spotlight do this on a Mac?
Yes. macOS indexes the whole startup volume, dates included, so Finder’s “Last modified” smart folders feel instant. But Spotlight is macOS-only, and it was built for a person typing into a box, not for an AI agent making hundreds of file lookups a minute.
Will a file I just saved show up immediately?
With a live index, yes. Freshness is about a millisecond in the typical case and under 30 milliseconds worst case, so a file becomes part of “recently changed” before the save dialog even closes: no re-scan, no waiting to catch up.
Do this today
Make “what changed” instant.
Install once. One signed installer builds the whole-drive index and auto-configures 19 AI clients: Claude Code, Cursor, Copilot, Codex, Windsurf, Zed, Cline and the rest. No folder-by-folder indexing settings, no JSON editing.
Ask by time. Everything changed in the last hour, today, or this week, across the whole machine, every repo and folder included. Because every date is already indexed, the window is a direct slice, not a scan.
Trust the freshness. A file you just saved counts as recently changed about a millisecond later, under 30 ms worst case. You never re-run a search to let it catch up.
Let your agent ask too. The same index answers over MCP, so Claude Code or Cursor can pull “what changed” in one call instead of grinding through folder listings. One warm index, every searcher on the machine.
Everything local is free forever.
Everything (the app plus the same index exposed to every AI client over MCP) is free forever, on all your devices, no card. Hosting your projects starts at $5.99/mo. Download for Windows.