Ungraded vs Grade 8.0 Adventure Comics #399 (1970): price difference
Adventure Comics #399 (1970) value — Ungraded $12 vs Grade 8.0 $70. Grade 8.0 sells for 5.83× Ungraded (+483%). Prices updated August 2026.
Medians of real sold listings per grade, updated August 2026 — how we compute values.
Grade 8.0 sells for 5.83× (+483%) the Ungraded price — a $58 difference per comic.
Grade 6.0 sells for 3.08× (+208%) the Ungraded price — a $25 difference per comic.
Should you get this comic graded?
Grading runs about $30 per comic all-in. On Adventure Comics #399 (1970), the jump from Ungraded to Grade 8.0 is worth $58 (5.83×) — if your copy grades at the top, that premium can cover the fee. A grade below the top one changes the math, so run your exact numbers first.
Run the grading break-even math →Values are estimates from real sales data — not appraisals or offers. Some links earn JunkPal a commission at no cost to you (disclosure).