I Tried to Replace ChatGPT With DeepSeek

A one-cent fix turned into a negative $759,935 quote. I gave ChatGPT and DeepSeek three practical jobs: reply to an unhappy customer, reconcile a messy cash report, and build a working quote calculator. I kept the original attempts, tested the outputs, and counted the correction prompts. Could DeepSeek actually take ChatGPT's job? The answer depends on the job—and the repair round changed the story. CHAPTERS 00:00 Can DeepSeek take ChatGPT’s job? 00:46 The test setup 01:28 The customer reply 04:13 The cash report 06:14 Build a quote calculator 08:22 Both miss one cent 09:04 DeepSeek repairs it 09:45 ChatGPT’s repair goes backwards 10:30 The second repair 11:12 The scorecard 13:20 Would I switch? ABOUT THE TEST Captured 13 September 2026, Australia/Brisbane. All company details, customer records and transactions are fictional; the tool responses and calculator results are real captured outputs from this session. Amounts shown are AUD. ChatGPT showed the Free plan with Think off. DeepSeek had Deep thinking and Smart Search off. The interfaces did not identify exact underlying model versions. Both received identical briefs in fresh chats; DeepSeek automatically converted the long pasted text to attachments. This is a small workflow comparison, not a universal model ranking. DeepSeek's cash response corrected its own initial table without a follow-up prompt. ChatGPT automatically offered two versions of the first calculator repair; Response 1 was selected before testing either. The final calculators both passed the ten predefined numeric cases, after different repair paths. What everyday job should I put them through next? Leave it in the comments. PRODUCTION Narration: Australian Steve, an ElevenLabs synthetic catalogue voice. Thumbnail: AI-created channel artwork. Original graphics and sound effects; illustrative stock footage from Mixkit / Envato. Stock footage is not test evidence. FOOTAGE CREDITS https://mixkit.co/free-stock-video/ty... https://mixkit.co/free-stock-video/ex... https://mixkit.co/free-stock-video/so... https://mixkit.co/free-stock-video/pe... https://mixkit.co/free-stock-video/yo... https://mixkit.co/free-stock-video/ha... https://mixkit.co/free-stock-video/wo... Licence: https://mixkit.co/license/#videoFree #ChatGPT #DeepSeek #AITools