Helio Guard vs ShadowLock
Both put an agent on Windows PCs and an extension in the browser, and both stop sensitive data reaching AI tools. ShadowLock is sold mainly to IT providers, per device. Helio Guard is sold per person, to businesses directly and through IT providers, and it knows each business's own clients.
Most comparisons are written by one of the two companies, and that company wins. This one is too. So every claim about the other product links to its own pages, with the date we checked, and we list where Helio Guard falls short. Checked 6 October 2026.
Side by side
| What | Helio Guard | ShadowLock |
|---|---|---|
| Who it is for | Small businesses directly, and IT providers for their clients | Mainly IT providers (MSPs), also internal IT teams 1 |
| Price | £1 a person a month, from 5 people. 14-day free trial, no card. Partner rates for IT providers. | $0.80 to $1.00 a device a month, no minimum, month to month 23 |
| Where it runs | Windows PCs, in Chrome and Edge | Windows 10 and 11; Chrome, Edge, Brave and Firefox 1 |
| What it checks | Pastes, sent messages, and files chosen for upload: Excel, Word, PowerPoint, PDF and text | Pastes, file uploads and typed prompts 14 |
| What it finds | Card numbers, bank details, National Insurance and NHS numbers, passwords, secret keys, lists of people, documents marked confidential, your own confidential words, and your own clients' names | API keys, US Social Security numbers, card data, health data, credentials and source code 4 |
| What it does with it | Takes it out, warns, stops it, or just records. Optionally, staff can send it anyway after picking a reason | Allow, warn or block per tool. Typed values are swapped for placeholders at the point of send 14 |
| Your own clients' names | Your client list, scrambled before it is saved. A client's name becomes "Client A" for the AI and comes back when the answer is copied | We found nothing about matching a business's own client list in its published material |
| Microsoft 365 | Not yet. It works alongside any Microsoft 365 plan | Scans for AI apps given access through Microsoft Graph 1 |
| Browser AI | Not yet | Switches off AI built into Chrome, Edge, Brave and Firefox 1 |
| Records kept | Checked on the PC. The text never leaves it. We keep the kind of data, the site, the person and the outcome, for 13 months | 90 days by default, configurable 1 |
Where ShadowLock is the better pick
ShadowLock covers more browsers (Brave and Firefox), switches off the AI built into browsers, scans Microsoft 365 for AI apps, and blocks personal AI accounts 1. Helio Guard does none of those yet. If those matter most, ShadowLock has them today. Helio Guard's answer is the data itself: it knows your clients' names, reads PDFs, Word and PowerPoint, and keeps the answer useful with stand-ins.
What Helio Guard does differently
- It knows your clients. Add your client list and Helio Guard swaps each name for a stand-in such as "Client A" before the AI sees it. Copy the answer and the real name comes back. The list is scrambled before it is saved.
- UK data, not US data. It looks for UK bank details, sort codes, National Insurance and NHS numbers. ShadowLock's published list leads with US Social Security numbers 4.
- Sold to the business too. A business can sign itself up at £1 a person. IT providers get partner rates and one view of every client.
- Policy agreed and dated. Each person agrees your AI policy once, and the date is kept for your records.
Where Helio Guard falls short
- Windows only for now. No Mac.
- Chrome and Edge only. Not Firefox, Brave or Safari.
- It does not yet switch off the AI built into browsers, such as Gemini in Chrome.
- It does not yet scan Microsoft 365 for AI apps that staff have given access to.
- It checks with fixed rules, not a language model. It is precise on the things it knows and does not guess.
- Scanned PDFs with no text in them have nothing to read, so they go through.
- It is new. It launched in 2026 and is in early access.
Common questions
Is Helio Guard cheaper than ShadowLock?
ShadowLock charges $0.80 to $1.00 for each device. Helio Guard charges £1 for each person, however many PCs they use. Which costs less depends on how many PCs each person has.
Does ShadowLock read PDFs?
Its pages say it intercepts file uploads and classifies the content. We found no list of the file types it reads. Helio Guard reads Excel, Word, PowerPoint, PDF and text files on the PC before they upload.
Sources
- ShadowLock home page. Checked 6 October 2026.
- ShadowLock vs Microsoft Purview, giving its price. Checked 6 October 2026.
- ShadowLock pricing. Checked 6 October 2026.
- ShadowLock AI prompt protection. Checked 6 October 2026.