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Mario M.
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Mario M.

Senior Data Quality Specialist | Search Evaluation & AI Training

⭐ Top Rated Specialist | 12,900+ Verified Hours | 100% Job Success I specialize in high-scale data management and precision-driven QA. With almost 13,000 hours of experience—including work on enterprise-level projects for global tech companies—I provide the reliability and technical accuracy that large-scale operations require. 💡 What I Do Best: • Data Integrity & Cleansing: I transform chaotic datasets into structured, audit-ready information. I have a zero-tolerance policy for inconsistencies. • AI Training & Annotation: High-precision data labeling and image annotation for computer vision. I deliver the high-quality "ground truth" data necessary for AI models. • Strategic Web Research: Detailed collection and verification of information. I focus on finding actionable insights, not just raw data. • Complex Data Organization: Advanced management of Excel, Google Sheets, and internal databases to streamline your workflow. 🛠 Why Collaborate With Me? • Proven Scale: 12,400+ hours is a guarantee of a battle-tested workflow. • Team Synergy: I have worked independently, as well as effectively within large international teams. This experience allows me to adapt quickly and provide value to clients in diverse projects. • Reliability: Whether it’s a short-term task or a longer project, I’m committed to delivering high-quality results on time, so you can focus on what matters most. 🌍 Ready to secure your data integrity. Available for immediate start on both short-term and long-term projects.

🇭🇷Slavonski Brod, Croatia$8/hr100% JSS5.00 (20)Since Aug 2020

Earnings and projects

MRR
$2

Last 6 months ÷ 6

World#180,741 / 412k
🇭🇷Country#289 / 807
Revenue, last 30 days
$0

Last 6 months: $10

Total earnings
$68k

Billed in all: $68k

World#58,115 / 412k
🇭🇷Country#161 / 807
Per project
$3.2k

$10 in the last 6 months

World#52,014 / 412k
🇭🇷Country#130 / 807
Projects, last 6 months
1

Across 2 contracts

100% fixed0% hourly
World#128,092 / 412k
🇭🇷Country#205 / 807
Projects in all
21

Across 23 contracts

13% fixed87% hourly
World#128,797 / 412k
🇭🇷Country#275 / 807

Earnings, last 30 days

$67.9kNothing earned in the last 30 daysBilled in all, before Upwork's fee · drag across the chart to see what was earned in any stretch
$66k$67k$68k$69kOct 8Oct 23Nov 7

Skill rankings: Top 42% in English to Croatian Translation

Ranked by MRR among everyone on Upwork with the skill.

  1. #37Structured Data53 freelancers · 🇭🇷 #1Top 70%
  2. #45English to Croatian Translation107 freelancers · 🇭🇷 #18Top 42%
  3. #288Lead Generation Analysis587 freelancers · 🇭🇷 #1Top 49%
  4. #396Spreadsheet Skills777 freelancers · 🇭🇷 #2Top 51%
  5. #416Image Annotation592 freelancers · 🇭🇷 #1Top 70%
  6. #1,289Data Management2,504 freelancers · 🇭🇷 #4Top 51%
  7. #2,140Data Cleaning3,952 freelancers · 🇭🇷 #2Top 54%
  8. #2,488Content Strategy4,813 freelancers · 🇭🇷 #4Top 52%