If you are a developer in 2026, your AI bill adds up fast. Claude Pro, ChatGPT Plus, Cursor, maybe some API credits on top — it is easy to cross $60 a month before you notice. So when I found Idlen in our directory, the pitch got my attention: earn money during the time you are already wasting waiting for AI to respond.
In this post I will explain what Idlen actually does, where it fits, and what the realistic alternatives are if you want to bring your AI costs down — whether by earning some of it back or just spending less in the first place.
What Idlen Does
Idlen is a free extension for VS Code, Cursor, and Windsurf, plus Chrome and Firefox. When you send a prompt to an AI tool — it works with Claude, ChatGPT, V0, Bolt, Lovable, Replit and more — there is always a wait while the model thinks. Idlen fills that wait with a curated developer-tool ad, and you get paid for the impression.
The mechanism is simple: the ad only appears during latency you would sit through anyway, so it does not slow anything down. Idlen claims typical earnings of €20–100 per month, with payouts via Stripe or PayPal, and a 10% bonus if you take your earnings as API credits instead of cash.
The privacy story is the part I checked first, because an extension sitting inside your editor is a big ask. Idlen says it never reads, stores, or transmits your source code or prompts — it only detects the action of sending a prompt, and any analysis (like reading your package.json to pick relevant ads) happens locally on your machine.
The honest caveats: your earnings scale with how much you actually use AI, so the €100/month figures come from heavy users. It is also a young product, and ad-based income is never guaranteed. Treat it as a discount on your AI subscriptions, not an income stream.
The Alternatives
Nothing else does exactly what Idlen does — monetizing AI wait time specifically is a new niche. But if your actual goal is "make my AI tools cost less," there are two families of alternatives.
Passive earners (make money while you work)
Brave Rewards — the Brave browser shows you privacy-respecting ads and pays you in BAT tokens. Fully passive once set up, but expect small amounts, and you are paid in crypto rather than cash.
Microsoft Rewards — points for searching with Bing (and using Copilot). Redeemable for gift cards. Low effort if Bing is already your default, pointless if it is not.
Honeygain / Grass — these pay you for sharing your unused internet bandwidth. They are genuinely passive, but the mechanism is very different from Idlen: you are reselling your connection, which comes with real considerations around your ISP's terms and what the bandwidth is used for. Read the fine print before installing.
The common thread: all of these earn small, variable amounts. None of them is designed around developer workflows the way Idlen is, and none will pick ads relevant to your stack.
Cost cutters (spend less instead of earning it back)
This side is less exciting but usually moves the needle more:
- Use free tiers strategically. Claude, ChatGPT, and Gemini all have capable free tiers now. Route your low-stakes questions there and save the paid subscription for real work. Our free tools section and free AI tools list are good starting points.
- Pay-as-you-go instead of subscriptions. If you use AI in bursts, API pricing (directly or through a router service) can come out well under a flat monthly plan. Do the math on your actual usage.
- Annual billing. Boring, but most AI subscriptions knock 15–20% off for paying yearly. On a $60/month stack that is real money — often more than a passive earner will pay you.
Quick Comparison
| Option | How you benefit | Realistic monthly value | Effort |
|---|---|---|---|
| Idlen | Ads during AI wait time | €20–100 (claimed, usage-dependent) | Install once |
| Brave Rewards | Browser ads paid in BAT | A few dollars | Install once |
| Microsoft Rewards | Points for Bing/Copilot use | Gift cards, ~$5–10 | Ongoing habit |
| Honeygain / Grass | Sell unused bandwidth | A few dollars | Install once |
| Free tiers + PAYG | Lower bill directly | $20–40 saved | Some discipline |
| Annual billing | Discount on what you pay | 15–20% saved | None |
My Take
If you are a developer who already spends hours a day waiting on AI responses, Idlen is the only option on this list that turns that specific dead time into money, and it is free to try — worst case you uninstall an extension. The bandwidth-sharing and rewards programs are fine but generic, and they will not know or care that you are a developer.
But the biggest savings are still on the boring side of the table: use free tiers for cheap tasks, check whether pay-as-you-go beats your subscription, and switch to annual billing. Stack Idlen on top of that, and offsetting most of one AI subscription per month is a realistic outcome rather than a marketing claim.
You can see screenshots, details, and the verified listing on our Idlen page, or browse more developer tools in the directory.