ScaledUiAmount (extension)

What it is

ScaledUiAmount applies a multiplier to a token’s displayed balance. Like InterestBearing, the raw on-chain amount never changes — amount_to_ui_amount multiplies it by the current multiplier. Unlike interest (which compounds over time), this is a single configurable factor the authority sets, ideal for rebases and stock-split-style adjustments.

Why it exists

Some assets need their unit value restated: a tokenized fund doing a 2:1 split, a rebasing stablecoin, a reward token that periodically scales. Rather than mint/burn against every holder (which breaks composability), the mint just changes one multiplier and every wallet’s displayed balance scales uniformly.

Byte layout

This is the payload of a ScaledUiAmount TLV entry (extension_type = 25, length = 56). The full on-chain entry adds the 4-byte TLV header (see the TLV layout primer).

Total payload: 56 bytes.

Why two multipliers + a timestamp

Like the fee config’s older/newer pattern, a multiplier change can be scheduled: set new_multiplier with a future new_multiplier_effective_timestamp, and decoders apply multiplier until that time, then new_multiplier. A correct UI picks the active multiplier based on the cluster clock.

Where you see it

Tokenized funds, rebasing tokens, and any asset that periodically restates unit value. Newer than most extensions (type 25), so adoption is early but growing for RWA products.

Common gotchas

• Floating point on-chain — rare and notable. The multiplier is an actual IEEE-754 f64 (8 bytes, little-endian). Most Solana fields are integers; this is one of the few f64s. Decode the 8 bytes as a double, not a u64.
• The raw amount is never scaled. As with interest-bearing tokens, reading a token account amount directly under-/over-reports value. Run it through amountToUiAmount.
• Scheduled multiplier needs the clock. Don’t display new_multiplier as current until new_multiplier_effective_timestamp has passed.
• Distinct from interest-bearing. Interest compounds continuously from a rate; ScaledUiAmount is a discrete factor the authority sets. A token uses one or the other, not both, for the same purpose.