Denker vs Jev Ultrafast
The same Google Flights search, by voice.
Summary
Jev Ultrafast is the open-source browser agent from Browser Use that searched Google Flights from Zürich to London in 7.1 seconds. We asked Denker, out loud, to run the same search in our own browser. Denker found the cheapest flight, then saved all 18 results as a spreadsheet and opened it. Jev is built for developers who want the fastest, cheapest browser step, while Denker is for people who want the finished result without writing code.
Key points
- Jev Ultrafast makes each browser step fast and cheap. It reads the page as a numbered list of controls and picks one action per request, so its demo run took 7.1 seconds. You run it from Python with Chrome and two API keys, and its README says it searches but does not select or book a flight.
- Denker starts from a spoken request in the browser you already use. We asked “Can we do the same?” Denker opened Google Flights in Dia, read the results and said the cheapest flight started at €69, with easyJet at 10:25 for €73 as the top non-stop pick.
- Denker keeps going after the search. One more sentence asked for the results as a CSV. Denker saved 18 flights to the Downloads folder and opened the file in Numbers, about 35 seconds after we first asked for the search.
In September, Browser Use released Jev Ultrafast with a short video: a browser agent searching Google Flights from Zürich to London in 7.1 seconds. The launch post had 3.2 million views on X when we recorded. We wanted to know what the same request looks like for someone who doesn’t write code. So we put Denker in live voice mode, asked it to find that video, and then asked it to do the same thing.
Watch: Denker repeats the Jev Ultrafast flight search by voice
Short transcript
Condensed speech and on-screen actions.
- 00:00So this is Denker versus Jev Ultrafast. Let’s first put Denker on live mode.
- 00:07Hey Denker, can you find the video for Jev Ultrafast? Denker opens the launch post on X.
- 00:18Great, can we do the same? Denker opens Google Flights for Zürich to London on Friday, November 6.
- 00:28Denker: I ran the same search on Google Flights. The cheapest flight from Zurich to London next Friday starts at €69, and the top non-stop pick is easyJet at 10:25 for €73.
- 00:33Nice. Can you put all this information in a CSV form and open it for me?
- 00:45Denker: I saved the 18 flights as a CSV in your Downloads folder and opened it in Numbers.
What Jev Ultrafast is
Jev Ultrafast is an MIT-licensed browser agent in the Browser Use GitHub organization. Its decisions come from Jev, a model by TypeSafe. On each step the agent turns the page into a numbered table of the visible controls. Jev then picks one operation, such as click, type or scroll, and the number of the control to use. A small text model writes words only when the agent needs to type.
This design is why it is fast. The default loop sends no screenshots, and each decision is one short request. In the launch demo the agent finished a one-way Zürich to London search in 7,073 milliseconds, and the launch post put the cost of that run at $0.0039.
Jev Ultrafast is a developer tool. You give it a goal and a start URL from Python. It drives Chrome through remote debugging and needs a TypeSafe API key plus a key for the text model. The README says the flight demo “does not select or book a flight” and that its timing is not a general reliability benchmark.
What we asked Denker to do
Denker is a desktop app for Mac and Windows. We held the voice shortcut to start live voice, so we could talk to it without pressing a key for each turn. Then we made three requests.
- “Can you find the video for Jev Ultrafast?” Denker opened the launch post on X in our browser.
- “Can we do the same?” Denker opened Google Flights, searched Zürich to London for next Friday and read the results back.
- “Can you put all this information in a CSV form and open it for me?” Denker wrote 18 flights to a CSV in Downloads and opened it in Numbers.
Denker worked in Dia, the browser we use every day, through the Denker browser extension. The search ran in a new tab next to our other tabs. The spreadsheet had one row per flight, with departure, arrival, airline, duration, route, stops and price in euros.
The second request shows the useful part. “Do the same” worked because Denker had just opened the Jev post, so it knew which search we meant. We never typed an airport, a date or a URL.
Side by side
The two tools are made for different jobs. The table compares what each one documents and what each demo finished with.
| Jev Ultrafast | Denker | |
|---|---|---|
| Made for | Developers building browser agents | People who want the task done |
| How you start | A goal and start URL in Python | Speak or type a request |
| Browser | Chrome via remote debugging | Your signed-in Chrome, Edge, Brave, Arc, Dia or Safari |
| Setup | Python, Chrome, TypeSafe and text model API keys | Install the app, add the browser extension (Safari: guided setup) |
| Flight demo result | A finished search | A spoken answer, then a CSV opened in Numbers |
| Work outside the browser | Not in scope | Files and desktop apps |
| Booking and payments | Demo stops before booking | Asks you before any payment or purchase |
| Timing in each demo | 7.1 s for one search | About 35 s for search plus spreadsheet, including speech |
| Price | Open source (MIT); needs TypeSafe and text model API keys | Free (25 on-screen requests a month), or Pro at €19/month; runs on the Claude Code, Codex or OpenCode you already use, whose charges are separate |
The timings come from one run each and measure different jobs, so they are not a benchmark. Jev’s 7.1 seconds covers one search. Denker’s 35 seconds covers two spoken requests, the search and the spreadsheet, including the time we spent talking.
Which one should you use?
Choose Jev Ultrafast if you build software that runs many browser tasks. Fast steps and low cost per run, $0.0039 in the demo, matter when a task repeats thousands of times, and an open-source loop lets you inspect and change every decision.
Choose Denker if you want the answer in your own apps. You talk, Denker works in the browser where you are already signed in, and the result lands where you need it: a reply, a file in Downloads, a spreadsheet you can sort. Denker asks before any payment or purchase, so spending stays your decision.
Try the same request
Install Denker on Mac or Windows and connect your browser in Settings › Connections › Browsers. Hold the voice shortcut for 2.5 seconds to start live voice, then ask for a search you run often, such as flights, prices or opening hours. When the results come back, ask Denker to save them as a spreadsheet.
On Windows, use Chrome, Edge, Brave or Arc; Dia and Safari are Mac only. A CSV opens in the spreadsheet app your computer uses for that file type.
Frequently asked questions
What is Jev Ultrafast?
An open-source browser agent from Browser Use. It reads a page as a numbered list of controls and uses TypeSafe’s Jev model to pick one action per step. Its launch demo searched Google Flights from Zürich to London in 7.1 seconds.
Is Denker faster than Jev Ultrafast?
We did not benchmark them. Jev’s demo measured one programmatic search. Our Denker recording covered a spoken search and a spreadsheet export in about 35 seconds, including speaking time.
Can Denker save web search results to a spreadsheet?
In our recording, yes. Denker saved 18 Google Flights results as a CSV in the Downloads folder and opened it in Numbers.
Does Denker book the flight?
We did not try booking. In this demo Denker only searched and exported the results, and it asks for your approval before any payment or purchase.
Does this work on Windows?
Live voice and browser control work on Mac and Windows, with Chrome, Edge, Brave or Arc on Windows. The recording was made on a Mac with Dia and Numbers, which are Mac only.
Do I need to code to use Denker?
No. You install the desktop app and ask by voice or text. Jev Ultrafast is aimed at developers and runs from Python.