Your inscription
| Component | vBytes | Cost (USD) |
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File size sweep
Same fee rate and BTC price — how total cost scales with content size.
| File size | Total vBytes | Cost (USD) |
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Why inscriptions are so much cheaper than they look
An Ordinals inscription is stored in the witness section of a taproot transaction. Since SegWit, witness data gets a weight discount: 1 weight unit per byte instead of 4, i.e. 1 vbyte per 4 bytes of content. A 50KB image therefore only adds about 12,800 vbytes to the reveal transaction, not 51,200 — a 4x discount before you even look at the fee rate.
Two transactions are required. The commit transaction locks funds to a taproot address that commits to your content's hash. The reveal transaction spends that output, actually publishing the content and creating the inscription. This calculator uses standard overhead estimates — ~154 vbytes for the commit tx, ~160 vbytes of fixed overhead on the reveal tx (inputs, outputs, script framing) — on top of the content's discounted witness vbytes, plus a 546-sat dust-limit postage output on each transaction (1,092 sats total, refundable/spendable, not a fee).
Fee rate matters more than file size for typical inscriptions
For anything under ~100KB, the fixed overhead and fee-rate multiplier dominate the total far more than the content size itself — a text inscription during a fee spike can cost more than a 150KB image during a quiet mempool. Check current network fees before timing a large batch of inscriptions.
Related: Network fees · NFT profit calculator · Bridge cost comparator
Frequently asked questions
How is an Ordinals inscription cost calculated?
Inscription content is stored as taproot witness data, which gets a ~75% weight discount versus normal transaction data — 1 weight unit per byte instead of 4, so 1 byte of content costs roughly 0.25 vbytes. Two transactions are needed: a commit tx (funds the reveal) and a reveal tx (contains your content and inscribes it). Total cost = (content_bytes / 4 + commit/reveal overhead vbytes) x fee rate, plus a small dust-limit postage output on each transaction.
Why do 50KB inscriptions cost so little even though Bitcoin fees can spike?
Because of the witness discount, a 50KB image only adds about 12,800 vbytes to the reveal transaction (51,200 bytes / 4), not 51,200. At a typical low-congestion fee rate of 1-5 sat/vB that's roughly $10-70 depending on BTC price, but the same inscription during a fee spike at 50-100+ sat/vB can cost several hundred dollars — mempool congestion matters far more than file size for anyone inscribing under ~200KB.
What is the practical file size limit for an inscription?
There's no hard protocol limit, but standard Bitcoin Core relay policy caps a single transaction's witness data around 400,000 vbytes (roughly 4MB of raw content once you account for the witness discount), and most miners/relays only forward standard transactions. Recursive inscriptions (content that references other already-inscribed inscriptions, e.g. for on-chain generative art) sidestep this by keeping each individual inscription small while composing large artworks from many small pieces.
What's the difference between the inscription fee and postage?
The fee (sats x vbytes) is what miners are paid to include your transactions in a block. Postage is a separate, tiny amount (typically the 546-sat dust limit) attached to the actual output that carries the inscription, so the UTXO isn't below Bitcoin's dust threshold and can be tracked/transferred later. Postage isn't burned or paid to anyone — it just sits in the inscription's UTXO as spendable BTC.
Does fee rate or file size matter more for cost?
For small-to-medium inscriptions (under ~100KB), fee rate dominates — a 10x jump in mempool fee rate (say 2 to 20 sat/vB) roughly 10xs your total cost regardless of file size. For very large inscriptions (500KB-4MB), file size starts to dominate because the witness vbyte count from content alone can exceed the fixed commit/reveal overhead by 100x or more. Timing your inscription for a low-fee window matters most for typical image/text inscriptions.