Get your LAN sycn groove on with Synthing + Localsend!

If you work in a small office, run a home business, or just have a bunch of devices floating around the house, then you’ve probably done this at some point:

Emailed a file to yourself.
Uploaded something to Google Drive just to download it on the computer right next to you.
Airdrop envy because not everyone’s on Apple.

Good news: your local network can do a lot of heavy lifting for you — no cloud required, no USB stick shuffling, no “what’s your email again?”.

In this post we’ll look at two brilliant (and free) tools for sharing files on your local area network (LAN):

LocalSend – perfect for quick, one-off transfers between nearby devices.
Syncthing – better for ongoing, automatic syncing between folders on multiple devices.

By the end, you’ll have a pretty good idea when to use each one, and why you might want both in your toolkit. Say goodbye to cloud link sharing, logins and AI data scanning your internal documents.

LocalSend: Share files to nearby devices

LocalSend is a free, open-source, cross-platform file sharing tool that allows you to share files to nearby devices.

Desktop and mobile device compatible - it just works the way it should. Support those who give or create value for you. Buy the Dev a coffee if you get value from this tool!

LocalSend: “AirDrop for everyone”

LocalSend is a free, open-source app that lets you send files and messages between nearby devices over your local Wi-Fi or LAN — with no internet connection and no cloud involved.

Think of it as AirDrop, but:

Works on Windows, macOS, Linux, Android and iOS
Doesn’t care what “ecosystem” you’re in
Uses end-to-end encryption so only sender and receiver can see the files

What devices does LocalSend run on?

Out of the box, LocalSend has apps for:

Windows
macOS
Linux
Android
iOS

As long as the devices are on the same local network (same Wi-Fi, same router), they can see each other and send files.

How LocalSend works (in normal-person terms)

LocalSend uses your local network to create a secure, peer-to-peer connection between devices. There’s no central server and nothing gets sent off to some mystery cloud.

Roughly:

Each device runs the LocalSend app.
The app advertises itself on the LAN.
Other devices running LocalSend see you in the list.
You pick a device, send a file.
The other person taps Accept, and the file lands on their device.

Transfers are fast because you’re only going over your LAN/Wi-Fi, not up and down to the internet.

Setting up LocalSend (step by step)

Here’s the basic process you can follow for most offices or home setups:

1. Install LocalSend

On phones/tablets:
- Open the App Store or Google Play and search for “LocalSend”.
On Windows/macOS/Linux:
- Head to the LocalSend website and download the version for your operating system.

Install it on every device you want to transfer files between.

2. Put all devices on the same network

Make sure everything is on the same Wi-Fi (or plugged into the same router/switch).
Guest networks can sometimes block device discovery, so keep an eye on that.

3. Open LocalSend on each device

Each device will show a device name (you can rename it to something sensible: “Tony-Laptop”, “Office-PC”, “Reception-iPad”, etc.).
Leave the app open in the background on desktops.

4. Send a file

On the sending device:

Open LocalSend.
Tap Send (or the plus icon).
Select the file(s) you want to send.
Choose the device you want to send to from the list.

On the receiving device:

You’ll see a pop-up saying “[Device] wants to send you files”.
Tap Accept.
Choose where to save (depending on OS).

That’s it. No logins, no accounts, no “verify your email”.

When LocalSend is handy

LocalSend really shines for ad-hoc, one-off transfers, like:

Passing photos from your phone to the work PC.
Sending a large PDF to someone at the next desk.
Moving a video from a tablet to a laptop without filling up your cloud storage.
Quickly sharing files to a guest machine, without giving them access to your whole OneDrive or Google Drive.

If you just want to move a thing from this device to that device right now, LocalSend is your friend. Send with Localsend (I just made that up) 😄

Syncthing

Synthing - securely share files on your LAN devices

Syncthing: your own private “always-on” file sync

Where LocalSend is about one-off transfers, Syncthing is about continuous syncing.

Syncthing is a free, open-source program that keeps folders in sync between two or more devices — laptops, desktops, servers, even some phones — without using a central cloud server.

You tell it:

“This folder on my laptop should match this folder on my office PC.”

…and it works quietly in the background, keeping everything up to date.

What devices does Syncthing run on?

Syncthing runs on:

Windows
macOS
Linux
Various BSD flavours
Android (via community apps)
iOS (via SyncTrain)

You can also run Syncthing on:

NAS boxes (e.g. a small home server or office NAS)
Cloud or VPS servers as a kind of “home base” (more on that below)

How Syncthing works

Under the hood, Syncthing:

Creates a unique device ID for each machine.
Lets you share folders between specific devices.
Uses encrypted, peer-to-peer connections to sync changes in real time or near real time.

There’s no central server you don’t control. You can use:

Just your LAN (everything stays inside your network), or
Your LAN plus the internet to sync with devices in other locations.

Setting up Syncthing on a simple LAN

A common small-office/home setup might be:

Laptop
Desktop PC
Maybe a NAS or always-on mini-PC

Let’s say we just want the laptop and desktop to share a “Projects” folder.

1. Install Syncthing

Go to the official site and download the installer for each OS.
Install it on both devices.

2. Start Syncthing & open the web UI

Run Syncthing; it will launch a local web interface (usually at http://127.0.0.1:8384).
You’ll see two main areas: Devices and Folders.

3. Exchange device IDs

On each machine:

Click Actions → Show ID to see the device ID.
Copy the ID and add the other machine as a new device.

You’ll see a notification on the other machine asking to approve the connection.

4. Create a shared folder

On one device:

Click Add Folder.
Give it a name (e.g. “Projects”).
Choose the folder path on that machine.
Tick the other device under “Share with Devices”.
Save.

On the other device:

You’ll get a prompt like “Device X wants to share folder ‘Projects’ — accept?”.
Choose where on that machine the folder should live, then approve.

Syncthing will then start syncing files between the two.

From now on:

Add a file to “Projects” on your laptop → it appears on your desktop.
Edit something on the desktop → the change is copied back to the laptop.

All over your LAN (or the internet, if you allow it), using encrypted connections and without any third-party cloud.

When Syncthing is handy

Syncthing is great when you want ongoing, automatic syncing, for example:

A shared “Office Docs” folder across multiple PCs.
Keeping your home desktop and work laptop in sync.
Backing up key folders from each machine to a NAS or home server.
Keeping scans, drawings or photos synced between machines without needing Google Drive or OneDrive.

If LocalSend is like passing someone a manila folder, Syncthing is like a shared filing cabinet that always has the latest version of everything.

Bringing Syncthing to iPhone

So far we’ve mainly talked about Syncthing on laptops, desktops and maybe a NAS. But what if you want the same “BYO cloud” experience on your iPhone, iPad or Mac, without diving into weird workarounds?

SyncTrain is a dedicated Syncthing client for iOS and macOS with a clean and easy to use interface.

What SyncTrain / Synctrain actually does

Synctrain builds on top of Syncthing and adds a few mobile-friendly tools:

Secure syncing with other Syncthing devices – your phone or Mac behaves like any other Syncthing node.
Selective sync – you don’t have to dump an entire folder onto your phone; you can pick specific files or subfolders.
On-demand access – browse a folder and download a file only when you need it, instead of filling up your device storage.
Media streaming – you can stream audio and video files straight from another device, handy if you’ve got big media libraries parked on a NAS or server.
iOS Files integration – synced folders are available via the Files app so you can open them in other apps.

One important note from the developer: like Syncthing itself, Synctrain is not a backup tool. If you delete a synced file on one device, that deletion will sync to the others. Always keep proper backups elsewhere (use Borgbase & Vorta for this - see Further Reading section below for the link).

Basic setup: adding your phone or Mac to your Syncthing network

The exact steps will vary slightly depending on your setup, but the flow is roughly:

Install Synctrain / SyncTrain
- On iPhone/iPad/Mac, open the App Store and search for “Synctrain” (or use your shared link).
- Install it like any normal app
Open the app and grab the device ID
- When you first open Synctrain, it will start its own Syncthing instance and show you this device’s name and ID (that long string Syncthing uses).
- This is just like the device ID you see in the standard Syncthing web UI.
Add your phone/Mac to another Syncthing device
- On your desktop/laptop where Syncthing is already running, open the Syncthing web interface.
- Add a new device, paste in the ID from Synctrain, and give it a friendly name like Tony-iPhone or Office-iPad.
- You’ll see a prompt back in Synctrain asking you to approve that connection – accept it.
Share one or more folders
- On your desktop Syncthing, choose a folder (e.g. Projects, Shared-Docs, Photos-Archive) and tick your phone/Mac under “Share with devices”.
- Synctrain will ask where to store that folder locally and whether you want full or selective sync.
Choose how you want it to behave on mobile
- For day-to-day use, most people:
  - Turn on selective sync so only important files actually live on the phone.
  - Use on-demand access to browse and fetch other files when needed.
- If you’ve got heaps of storage on an iPad or MacBook, you might choose to fully sync certain folders.

LocalSend vs Syncthing: which should you use?

The short answer: they solve slightly different problems, and you’ll probably be happiest running both.

Here’s a quick comparison:

Use case	LocalSend	Syncthing
One-off file transfer	Excellent	Overkill
Continuous folder sync	Not designed for it	Excellent
Works fully offline on your LAN	Yes (localsend.org)	Yes (can be LAN-only) (Wikipedia)
Setup complexity	Very simple	A bit more setup, then mostly hands-off
Platforms	Win/macOS/Linux/Android/iOS (localsend.org)	Win/macOS/Linux/*BSD/Android/iOS (via apps) (Wikipedia)
Best for	“Send this file to that device right now”	“Keep these folders in sync across devices”

When you’d choose LocalSend

Use LocalSend when:

You’re in the same room or office and just need to fling a file from one device to another quickly.
You regularly move photos or videos from your phone to your PC.
You’re working on multiple platforms (say, Android phone + Windows desktop + iPad) and want a simple way to move stuff between them, no accounts, no cloud.

It’s the digital equivalent of handing someone a USB stick, just without the actual stick.

When you’d choose Syncthing

Use Syncthing when:

You want shared folders across devices that stay in sync automatically.
You’re sick of juggling which version of a file lives where.
You’d like a “BYO cloud” for your home or office — your data, your hardware, no subscription.

For example, you could:

Run Syncthing on all your computers, plus a NAS or always-on mini-PC.
Use that always-on machine as your “hub” (but it’s still peer-to-peer, not a central cloud you don’t control).

And if you don’t want to run a physical box at home, you can even spin up a small virtual machine using a service like Shells.com (see link below), which gives you an always-on cloud computer you can access from any device.

Install Syncthing on that VM, and you’ve effectively built your own private “cloud drive” — without handing your files to Google, Apple, Amazon, Dropbox or Microsoft.

Why you might just set up both

Here’s the sweet spot for most small offices or home setups:

LocalSend for:
- Quick, messy, human stuff — “Can you send me that photo?”
- Moving files off your phone after a site visit or inspection.
- Passing large files around without clogging the internet connection.
Syncthing for:
- Shared team folders on your LAN.
- Keeping project files the same on your laptop and desktop.
- Quiet background backups to a NAS or VM.

They don’t clash. They don’t fight. They just handle different jobs:

LocalSend is the courier.
Syncthing is the filing system.

Conclusion

You don’t have to live in your cloud provider’s ecosystem if you don’t want to. Localsend & Syncthing give you choices depending on your workflows and security environment. Dont want AI scanning or reading confidential docs? Share them locally, fast and securely with Synthing and localsend.

Between LocalSend and Syncthing you can:

Move files around your LAN fast, without uploads and downloads.
Keep key folders synced across devices automatically.
Use your own hardware (or your own VM) as storage, instead of renting space from the big players.

If you’re running an office, setting these up is one of those tech upgrades that pays off every day — fewer “Can you email that to me?”, fewer USB sticks, fewer mystery versions of files, fewer emails and faster turnarounds.