DataMani — Free Data Manipulation Tools

What it does

Free, privacy-first web tools for Data Analysts. Merge Excel files, split CSVs, convert formats and more — all processing happens in your browser. No uploads, no signup.

All processing happens in your browser . Files are never uploaded. No signup required. Combine multiple Excel (.xlsx, .xls) and CSV files into one workbook. Union merge handles different column schemas automatically. Split large CSV files into smaller chunks by row count. Downloads as a ZIP archive with numbered parts ready to use. Convert .xlsx or .xls files to CSV. Multi-sheet workbooks export as a ZIP with one CSV per sheet, preserving all data. Convert CSV files to JSON array format. Each row becomes an object with column headers as keys. Perfect for APIs and developers. Remove duplicate rows from CSV or Excel files. Tells you exactly how many rows were removed before downloading the…from data-mani.com

• CF
  CSV file merging2019 · mightymerge.io · ▲29

  An intuitive CSV Importer and CSV File Merging tool.

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  CSV Tools Online2025 · csvtoolsonline.com · ▲13

  Powerful data tools. No coding.

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  Cell Stitch2025 · cellstitch.com · ▲3

  Merge Excel files & unlock tools for smarter spreadsheets!

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  ZippyRows2025 · zippyrows.com · ▲8

  Free csv editor & data tools

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  SheetRowsFeb 2026 · sheetrows.com · ▲2

  100% Free Private Excel tools | Zero data leaves your device

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  Pluck2025 · pluckdata.com · ▲6

  Instant data analysis for any webpage

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  SimCity, but with Permits▲877

  A free city-building game in your browser. You are the mayor. You know what the city needs. Now get it past the zoning board, the neighbors, the appeals court and the next election.

  Life & fun · 22h ago · permit.petercai.com

• IV
  I've been paying for a rural Tanzanian's education for 10 years▲778

  Life & fun · 13d ago · tanzaniaeducationproject.org

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  Bigwords.page – Turn any screen into a sign. The URL is the app▲728

  Turn a phone, tablet or TV into a sign. Type a message and it fills the screen: welcome signs, timers, Wi-Fi passwords and more. No app, no account, free.

  Life & fun · 14d ago · bigwords.page

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  Guitoro, a virtual guitar you strum with your keyboard▲573

  Play a free virtual guitar online with your keyboard or by touch. Slow songs down and see every chord, string and strum. Acoustic, classic, electric and bass.

  Life & fun · 8d ago · guitoro.com

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  See *almost* any carriers phone settings▲432

  Carrier settings from iPhone, Pixel and Galaxy firmware, decoded and compared: APNs, VoLTE, 5G and Wi-Fi Calling per carrier, and what each build changed.

  Life & fun · 12d ago · carrierexplode.com

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  The whole Solar System and every tracked satellite, live in the browser▲407

  Life & fun · 22d ago · space.bl2.net

• IR
  I replaced a $120k bowling center system with $1,600 in ESP32s▲2,935

  I might be the only SRE on Earth with his own bowling center. It's a more in-depth gig than you'd think. My family and I bought an abandoned 8-lane bowling center in the rural mid-west. In our small town there weren't many recreation options for families. You've heard of a food desert? This is an R&R desert. It had been abandoned for a good reason. The roof leaks, the electrical system was constantly surging, and my 70-year-old bowling equipment (still) doesn't work perfectly. The system that keeps your score is particularly interesting to me. It's the thing you watch during your game, but…

  Life & fun · Jul 2026

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  Elevators▲1,680

  How elevators push your buttons

  Life & fun · Jul 2026 · john.fun

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  18 Words▲1,160

  Play 18 Words, the free daily word puzzle. The official home is 18words.com. Tap Play now to open today

  Life & fun · Jul 2026 · 18words.com

• BA
  Bento - An entire PowerPoint in one HTML file (edit+view+data+collab)▲1,033

  Over the past few months, our team has been building more and more slidedecks using web frontend technologies with coding harnesses like Claude Code, but a common complaint is to make even small edits we need to edit the code either manually or via the harness. To avoid this loop, I ended up creating Bento, a single HTML file with everything you need in a slide tool including animations and shared editing. There's no install or cloud login, everything works offline. The default deck is around 560 KB and it doesn't need to fetch anything once you got it. Open it in a browser and then you can…

  Dev tools · Jul 2026 · bento.page

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  Getting GLM 5.2 running on my slow computer▲937

  A few days ago I found myself trying out GLM 5.2 and was really positively impressed. The capabilities and security I was getting from this LLM are similar to those I've gotten from models like Claude or GPT, and this really surprised me. But then I thought, "I wonder how it would work on a normal computer like mine," and above all, "I wonder if it would work without going into OOM on a computer like mine." So I started working with the help of agents to test this possibility. I started converting the model to int4, understanding MTP usage, and if possible implementing DSA for long context.…

  AI · Jul 2026 · github.com

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  OpenSEO▲928

  Hello! For the last 2 months, I've been building OpenSEO. It's a user friendly UI wrapping the DataForSEO API which has high quality SEO data for keywords, backlinks, AI SEO and competitor research. Instead of paying $100+ per month, you buy DataForSEO credits and pay only for usage. The coolest thing about the project so far has been hearing about what people are building on top of it. People are using coding agents to quickly integrate with Google Search Console, Google Ads and building their own AI SEO and reporting features. Many were already building their own custom solutions around…

  Dev tools · Jul 2026 · openseo.so