Community price on backpack.tf: 7.00–8.00 keys, last changed 2025-12-19 (10mo ago). The live quote above, 7.12 keys, is inside the community’s range and last moved 25d ago. They are different measures: the quote is what traders and bots are asking and bidding on the classifieds right now, and it moves for thousands of items every day; the community price is a suggestion accepted by vote, which changes only when someone argues it should. A quote well away from the vote is usually a price that is about to be re-argued. Community prices from backpack.tf, read under an hour ago.
Steam Market asking price: $17.63 — the lowest of 11 listings for the Sandy effect when we looked on 2026-10-07 01:47 UTC (6d ago). This is what a seller is asking, not what anything sold for. Steam pays out in Steam wallet funds, not cash, and Valve takes roughly 15% at the till — so asking prices there run well above the 7 keys, 7.33 ref shown above, which comes from the keys-and-metal market on backpack.tf. The two are different markets and are never blended. Steam lists the item as “Unusual Professor Photon”, with no effect in the name — the effect comes from the individual listing.
Price history
14 observations
Interactive chart. Press the left and right arrow keys to move along the series, Home or End to jump to either end, Escape to clear.
The key axis converts at today's rate. Prices are recorded in metal, so a line that is flat in keys followed the key rate rather than standing still.
Sandy Professor Photon sell price, 2025-12-20 to 2026-09-18: 14 observations, from 6.91 keys to 7.12 keys.
Observed (UTC)
Sell
Buy
20 DEC 2025 · 18:06 UTC
6.91 keys
5.45 keys
5 MAR 2026 · 00:42 UTC
6.86 keys
5.26 keys
10 MAR 2026 · 10:10 UTC
7.08 keys
5.65 keys
11 APR 2026 · 16:32 UTC
7.10 keys
5.68 keys
29 APR 2026 · 14:30 UTC
6.65 keys
5.20 keys
9 MAY 2026 · 10:33 UTC
7.04 keys
5.11 keys
17 MAY 2026 · 20:35 UTC
7.36 keys
5.98 keys
10 JUL 2026 · 08:44 UTC
6.39 keys
5.69 keys
20 JUL 2026 · 14:44 UTC
6.94 keys
6.03 keys
27 JUL 2026 · 00:46 UTC
6.81 keys
6.23 keys
5 AUG 2026 · 11:12 UTC
7.02 keys
6.44 keys
11 SEP 2026 · 16:10 UTC
7.09 keys
6.16 keys
14 SEP 2026 · 00:08 UTC
7.07 keys
6.15 keys
18 SEP 2026 · 16:07 UTC
7.12 keys
6.19 keys
Price history in numbers
14 readings since 20 Dec 2025
Over the last 30 days the Sandy Professor Photon's sell price ranged from 7.07 keys to 7.12 keys and is up 0.6% after 1 move. Over a year it ranged from 6.39 keys to 7.36 keys (up 2.9%). Today's 7.12 keys sits in the upper third of its range: the lowest we have recorded is 6.39 keys (10 Jul 2026) and the highest 7.36 keys (17 May 2026). The price has moved 13 times since we began recording it — about once every 21 days.