🔗 Bitcoin Large OP_RETURN Explorer

About Large OP_RETURN Explorer

Historical OP_RETURN Limits

Bitcoin's OP_RETURN size limits have evolved significantly over time:

• March 2014 (Bitcoin Core v0.9.0): OP_RETURN introduced with a 40-byte data payload limit
• July 2015 (Bitcoin Core v0.11.0): Increased to 80 bytes of data payload
• February 2016 (Bitcoin Core v0.12.0): Allowed multiple data pushes with a 83-byte total script size limit
  • This 83-byte limit accounts for script overhead:
    • 1 byte: OP_RETURN opcode (0x6a)
    • 1-2 bytes: Push opcode(s)
    • 1 byte: Length byte
    • 80 bytes: Maximum data payload
• October 2025 (Bitcoin Core v30.0): Increased to 100,000 bytes (100 KB) of data payload

What This Repository Collects

This repository scans for OP_RETURN outputs with total script size > 83 bytes, which means:

• Data payload exceeds 80 bytes (the historical limit from 2015-2025)
• Total script size exceeds 83 bytes (the limit from 2016-2025)

The 83-byte threshold ensures we capture all OP_RETURNs that exceeded the historical limits, regardless of whether they used single or multiple data pushes. This includes both:

• Scripts that exceeded the 80-byte data limit in a single push
• Scripts that used multiple pushes to exceed the 83-byte total script size limit

Important Note

The distinction between 80 bytes (data) and 83 bytes (script) is important:

• 80 bytes = Historical data payload limit (what users could embed)
• 83 bytes = Historical total script size limit (what Bitcoin Core enforced)
• Our scanner checks > 83 bytes (total script size) to capture all historically "large" OP_RETURNs